From what I've read over the years, Amix had a reputation of simply being a damn good implementation of Unix.
I don't think anyone "still" runs it, but the tremendous efforts of Failure here at Amiga.org have brought it back from the dead, so a few of us have started running it
(I haven't booted my Amix partition in ages, though). The marketing brochure at the Amix Wiki describes some clients.
In the Deathbed Vigil, Dave Haynie talks about Amix a bit. Sun was interested in using the 3000UX as their OEM Unix 68K platform, but Commodore management managed to botch the deal - twice. One of the Amix developers is also in DBV, and describes the last few days of the gutted Amix team.
