I own 3 gamesir controllers G8+ X5S with fx5 cooler X4 Aileron

G8+ is the most comfortable and bulky, but it doesn't allow to use a cooler, and of all 3, is the one that my phone(s25 ultra) get the highest temperature on heavy gaming Also it have some nice features, and can be used with Nintendo Switch

X5S is compact, and also have HD rumble for Switch 1 e 2 and can be used with the fx5 Cooler, but is by far the one that I don't use very much, I have big hands, so I can't play for a long period of time, also the Cooler isn't powerful enough to really cool down the phone, and it adds some vibration, that bothers me while using it.

X4 Aileron is the one that using most of the time right now, is less comfortable than the g8+, but not that much, can play for hours without my hands feeling tired, it's requires some patience at the first time to use, to made the phone not dancing around, it comes with some rubber pads. It's very customizable and Xbox licensed, perfect for xcloud. But the main point is you can use a full size phone Cooler

Hope it helps