I picked up a block letter a few weeks ago to relive some of those old tones again. Plugged in and played along with a few In Flames albums, I couldn't tell where my tone ended and the albums began. It's not modern, refined or very "tight" by today's amp standards but damn it sounds so good. All those In Flames albums were absolutely incredible
For me the quintessential 5150 tone was Arch Enemy's Stigmata album. Alongside In Flames, I think of Arch Enemy using the 5150. Arch Enemy I think had a bit better guitar tone though.
Honorable mentions:
Opeth's album "My Arms, Your Hearse" used a 78' Gibson SG & 74' Gibson LPC thru a 5150 with the Peavey cab.
Opeth's album "Still Life" had the same guitars and a 5150, recorded at Studio Fredman.
Most of The Haunted's Revolver was recorded at Studio Fredman using their personal 5150s. They had a DVD for Revolver with a close up of their settings, wish I could find it online
Job For A Cowboy used 5150's on their early stuff, which is just a disgusting display of riffage