Up until now I was using an XBOX One controller with a clip for attaching your phone, which worked well but was quite unergonomic. I had to keep my wrists in an awkward angle, which made my fingers go numb after a short amount of time.
Now I got me the Gamesir X2 Pro and I couldn't be happier. The Switch form factor is SO MUCH MORE ergonomic and with the USB C connection there's no latency at all. It's finally fun to play emulators on the phone (or to stream from my gaming PC).
The buttons are rather clicky, so the acustics can get a little annoying, but haptically they feel great. The build quaility is pretty satisfying all around.
Totally recommended if you're into phone gaming.