Anecdotally, as a brawler player, I don't generally have problems playing on Sahara, but Alleys gives me no end of trouble. Which seems to be backwards from conventional wisdom. But that could also be because there are a few rooms in alleys where enemies never seem to stop spawning on you until you die.
I understand that my word isn't technically credible, as I have little specific proof of my performance in any given match, and only a few small recordings. But again, anecdotally, as someone who mains Brawler, I do extremely well in almost every match I play, whether it be against 'pubs' or against other members of BSB, DAD, SK, ROAM, Dirtnap, whatever, provided I can actually ass myself into playing seriously and have been warmed up, like anyone else.
Blah blah anecdotes blah blah not scientific enough - believe me, I understand if I can't back up my words with hard numbers there's no foundation to what I'm saying. I have been playing Brawler since CB1 (I played.. something in Alpha) and across whatever buffs or nerfs or what have you to Brawler I have been pretty consistently able to make it work well enough for me that I have little impetus to play other classes, apart from the small urge to level other things up.