I find 85dB far too intense. Man, I've mixed quite a few live gigs that hover around 87dB SPL (A-weighted, slow), since it used to be a limit of sorts at the concert hall in my previous school. IIRC you can take it for about 30 minutes, after that you'll possibly be damaging your hearing. It also makes a live rock band sound so bland that you'll find 30 minutes of it to be quite enough.
I mix really, really quiet. Haven't measured, but I'm betting it's around 60dB max, since it's a little bit quieter than normal conversation. I guess I'm a little bit paranoid that I'd possibly disturb the neighbors if listened louder, and honestly, I'm pretty sure I could crank it up a little bit and it'd be completely fine. That said, I actually got one noise complaint at a previous apartment due to music being too loud, but it had to do with being drunk and was pretty funny.