| Musician | Appearances |
|---|---|
| Steven Wilson | 6 albums |
| Nick Beggs | 5 albums |
| Theo Travis | 5 albums |
| Adam Holzman | 4 albums |
| Guthrie Govan | 3 albums |
| Marco Minnemann | 3 albums |
| Ninet Tayeb | 3 albums |
| Craig Blundell | 2 albums |
| Dave Kilminster | 2 albums |
| Tony Levin | 2 albums |
| Mike Outram | 2 albums |
| Jordan Rudess | 2 albums |
| Sand Snowman | 2 albums |
| Leo Blair | 1 album |
| Ben Castle | 1 album |
| Mark Feltham | 1 album |
| Nic France | 1 album |
| Dave Gregory | 1 album |
| Trey Gunn | 1 album |
| Steve Hackett | 1 album |
| Gavin Harrison | 1 album |
| Sophie Hunger | 1 album |
| Jakko Jakszyk | 1 album |
| Katherine Jenkins | 1 album |
| David Kollar | 1 album |
| Pat Mastelotto | 1 album |
| Robin Mullarkey | 1 album |
| Alan Parsons | 1 album |
| Markus Reuter | 1 album |
| Dirk Serries | 1 album |
| Clodagh Simonds | 1 album |
| Jeremy Stacey | 1 album |
| Paul Stacey | 1 album |
| Chad Wackerman | 1 album |
| Michio Yagi | 1 album |