Almost every band in this music has a dividing line running through its catalogue: a singer who left, a keyboard player who was replaced, a year when the sound changed. Ask which is the best era of prog rock bands like these and you start an argument that has been running for decades. This hub sets out the facts behind thirteen of those arguments – when the change happened, who was in each line-up, what the records did – and links to the full comparison for each band. The verdicts are yours; what follows is the evidence.

What actually changes when a band changes

Three things separate one era from another, and it helps to know which one you are arguing about. A singer changes the voice at the front and usually the words, as with Genesis, Marillion, Kansas and Queensrÿche. A writer changes what the band is about: when Roger Waters left Pink Floyd, or Peter Bardens left Camel, the loss was of a co-author, not only a player. And sometimes nobody leaves at all and the instruments change, which is what happened to Rush in the 1980s and to Opeth in 2011. Most of the debates below mix at least two of the three.

Genesis: Gabriel or Collins

The most argued-over split in the genre. Peter Gabriel left at the end of the Lamb Lies Down on Broadway tour in May 1975, although the departure was made public only on 15 August that year. The band auditioned hundreds of singers, briefly considered carrying on as an instrumental group, and then found the answer behind the drum kit: Phil Collins sang “A Trick of the Tail”, released on 13 February 1976, and Bill Bruford played drums on the tour that followed. Steve Hackett left in 1977, and from … And Then There Were Three… (1978) onwards the band was a trio.

Read the full comparison: the Gabriel era vs the Collins era · Genesis: Gabriel or Collins band guide

Pink Floyd: Waters or Gilmour

Pink Floyd has two dividing lines, not one. The first is 1968, when Syd Barrett, who had written most of the first album, left the group. The second is December 1985, when Roger Waters told the record companies that he had left, believing the band to be finished; David Gilmour and Nick Mason disagreed, made A Momentary Lapse of Reason in 1987 and reached an agreement with Waters over the name in December of that year. Both eras sold enormously, which is part of why the argument never ends.

Read the full comparison: the Waters era vs the Gilmour era · Pink Floyd: Waters or Gilmour band guide

Marillion: Fish or Hogarth

Fish left Marillion in late 1988, after four albums. The band auditioned singers while already writing the next record, chose Steve Hogarth, and released Seasons End in 1989; it reached number 7 on the UK albums chart. Most of the music had been written before Hogarth arrived, and the lyrics of that album came largely from an outside writer. Hogarth has now been in the band far longer than Fish was, which is the fact the argument usually forgets.

Read the full comparison: the Fish era vs the Hogarth era · Marillion: Fish or Hogarth band guide

Rush: the 1970s or the synth era

Here nobody left. The same three musicians moved from the long suites of the 1970s to the keyboard-led records of the 1980s, from Moving Pictures (1981) through Signals, Grace Under Pressure, Power Windows and Hold Your Fire, and then back towards guitars at the end of the decade. It is the clearest case in this list of an era defined by instruments rather than by people.

Read the full comparison: the 1970s albums vs the synth era · Rush: the 1970s or the synth era band guide

Yes: which line-up

Yes has had more line-ups than any band here, and at least four of them have their supporters: the 1971–72 group with Bill Bruford, the 1972–74 group with Alan White and Rick Wakeman, the 1974–76 group with Patrick Moraz on keyboards, and the 1983 band of 90125, with Trevor Rabin and Tony Kaye, which gave Yes its only American number one single. In between sits Drama (1980), the one album with Trevor Horn singing and Geoff Downes on keyboards.

Read the full comparison: every Yes line-up explained · Yes: which line-up band guide

King Crimson: which era

Robert Fripp is the only constant, and the band has been rebuilt from scratch several times: the 1969 group of the first album; the 1972–74 band with John Wetton, Bill Bruford and David Cross; the 1981–84 band with Adrian Belew and Tony Levin; the double trio of the mid-1990s; and the group of 2014–21 with three drummers at once. Choosing an era here is less a matter of taste than of deciding which of several different bands you are looking for.

Read the full comparison: King Crimson line-ups explained · King Crimson: which era band guide

Dream Theater: Portnoy or Mangini

Mike Portnoy, who co-founded the band, left in September 2010 while the group was on tour. Mike Mangini was chosen in an audition filmed and released to the public, and played on A Dramatic Turn of Events (2011) and the four albums that followed, among them the Grammy-winning “The Alien”. In October 2023 Dream Theater announced Portnoy’s return, and he is on Parasomnia (2025), which makes this the only debate in the list with a third act.

Read the full comparison: the Portnoy era vs the Mangini era · Dream Theater: Portnoy or Mangini band guide

Jethro Tull: which era

Jethro Tull moved through more styles than most: the blues band of This Was (1968), with Mick Abrahams on guitar; the rock band of Aqualung (1971); the single-track albums of Thick as a Brick (1972) and A Passion Play (1973); and the folk-rock records that begin with Songs from the Wood (1977). Ian Anderson is the constant, and each of those phases has readers who would start a newcomer there.

Read the full comparison: which Jethro Tull era to start with · Jethro Tull: which era band guide

Camel: Bardens or Latimer alone

Camel was built on the writing partnership of Andrew Latimer and Peter Bardens. Bardens left after Breathless (1978), announcing his departure before the tour for the album, and from then on Camel was Latimer’s band, with changing personnel around him. It is the clearest example here of a split where the argument is really about a co-writer rather than a front man.

Read the full comparison: the Bardens era vs the Latimer years · Camel: Bardens or Latimer alone band guide

Porcupine Tree or Steven Wilson solo

A different kind of comparison: not two eras of one band, but a band and the solo catalogue of the man who leads it. Steven Wilson began releasing albums under his own name in 2008, Porcupine Tree stopped touring after The Incident (2009), and the band returned in 2022 with Closure/Continuation. Anyone arriving today has two shelves to choose from, and they are not the same shelf.

Read the full comparison: Porcupine Tree vs the solo albums · Porcupine Tree or Steven Wilson solo band guide

Opeth: before or after Heritage

Opeth’s dividing line is a single record. Watershed (2008) was the last album with growled vocals; Heritage (2011) had none, and the band has kept to that path since. The line-up barely changed, which makes this the purest case of a band changing era by decision rather than by departure – and the one where the two camps of listeners overlap the least.

Read the full comparison: Opeth before and after Heritage · Opeth: before or after Heritage band guide

Kansas: Walsh or Elefante

Steve Walsh left Kansas in 1981; John Elefante replaced him and sang on Vinyl Confessions (1982) and Drastic Measures (1983), writing several songs along the way. Walsh returned in the mid-1980s. Two members, Phil Ehart and Rich Williams, have played on every Kansas album, which is the thread that holds the eras together.

Read the full comparison: the Walsh era vs the Elefante years · Kansas: Walsh or Elefante band guide

Queensrÿche: Tate or La Torre

Geoff Tate sang on the albums that made the band’s name, Operation: Mindcrime (1988) and Empire (1990). He and the band parted in June 2012 and Todd La Torre took over, first on the self-titled album of 2013. For a period there were two touring versions of the group; an agreement in April 2014 settled who would carry the name, and Tate kept the right to perform Operation: Mindcrime in full.

Read the full comparison: the Tate era vs the La Torre years · Queensrÿche: Tate or La Torre band guide

How to use this list

If you are new to a band, the useful question is not which era is better but which one to enter through, and each article ends with that answer: one album per era, with what it will and will not prepare you for. If you already know the catalogue, the articles give you the dates, the line-ups and the chart figures to argue with. And if a change of line-up made a band better rather than worse, there is a whole piece on that: the best line-up changes that improved a band.

Go deeper

For arguments between bands rather than within them, see prog rock’s greatest debates, band vs band. For the records themselves, start with the best progressive rock albums of all time, or browse the guides to each band linked above. The full history behind these bands, era by era, is what my Beyond the Sound series is for: Beyond the Thames covers the British bands, Beyond the Atlantic the American ones, and Beyond the Decades the modern era.

Want the whole story, era by era? The books map every scene →

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