I was one who fought off 6-MP for some time - but that's because when it was first offered to me it was a "brand new thing which seems to be working well..." just like a new model car, I wanted the bugs worked out before I bought into it! lol
The dosing, watching blood levels, all that - it's relatively safe, now, I feel (though some will always react to any medication!) and I would take it without blinking if my GI recommended it at this point.
I think it works well for the majority - so well, those folks aren't sitting around posting about
UC.... (my thought, anyway.)