Hushpuppy

The thing is tho, Mccrees full stun-fan-roll-fan combo can do 800 damage and he stuns you instantly with no time to react, while Mei's freeze headshot thing does maybe 200 and can be avoided by jumping away once she starts to spray you.

but you can easily avoid flashbang by not getting in mccrees face. with mei, she slows you down with ice. maybe im being biased because i fucking hate mei but idk. on the topic of op characters, roadhogs heal is too damn op. healing 200-300 hp every 5 seconds...

The more you play, the more you get use to Mei and how to deal with her (honestly you can mostly just ignore her as long as you stay out of range of her primary), and Mccrees are usually going to flank you so they're in your face before you even know he's there. Also, think of all that healing from roadhog as free ulti charge :D