Reposting a PSA I made on /v/:

I bought a bunch of Sega-style controllers recently. I think it's important, if you're also an autistic person who will buy a controller specifically for 2D games like shmups and fighters, for you to know that both the 8bitdo M30 and the Retro-Bit Sega Saturn controllers fucking suck. They suck fucking dick. People say good things about them but they're wrong. They fucking suck. The 8bitdo has almost no pivot and the Retro-Bit Saturn is mushy as shit.
The ONLY good one is the Retro-Bit Sega Genesis controller. It's genuinely excellent. The GENESIS one, NOT the Saturn. Both the wireless and wired versions are fine (but make sure it's the 8-button version if you want shoulder buttons). No one talks about it, but it's basically perfect in every way. The dpad has a nice tactile feeling while also rolling easily. No chance of misinputs. It also has shoulder buttons so there's literally no reason to not get it over their terrible Saturn controller. GET THE GENESIS CONTROLLER, THIS IS YOUR WARNING.