It's one of the best hardware purchases I've done in years. It's surprising how well it managed to balance "It just works" with "You can still customize/modify/install things you need.". It's not perfect (screen could be better, battery life could be better, it's a bit chunky).
> And how do you use it?
I use it as a "secondary" gaming device. I have a gaming PC where I play games with a Steam library. Since Deck shares that library and seamlessly syncs save games, I can sneak in some game time before sleep, when travelling or when commuting with a lot of game time. When I have more time, I usually move back to my PC where the games and saves are waiting for me.
The fact that it goes instantly to sleep and suspends games is amazing - it really reduces a lot of friction for short gaming sessions because you don't need to wait for games to load.
If you don't play games though... it's probably pointless to get one.