I just used my (new to me) JCM 800 bass series 50 watt with my Ampeg 810e over the weekend to finish some recordings that have been languishing for a year (a bad DI ground loop pretty much ruined my previous takes, then the computer bit the dust, etc, etc). My recordist/guitarist, Greg, was eager to give it a shot because my Mesa (Bass 400) was eating the crummy drum kit/heads for lunch. Mic'ed with my EV RE20, I'm pretty pleased with the result, which is much better in the midrange for what we need the bass to do. For me, the coolest part was that I could be stuck in a room with the rig for 3 hours and not have massive ear-ringing afterward.
I took a photo for documentation purposes (sorry, blurry phone cam shot):
