It's growing on me very quickly. Been playing a lot of Chrono Trigger on it right now. It's a lot more comfortable to hold than the Steam Deck too. Plus, it supports both Android and Linux. There are already versions of Rocknix and Batocera available for it. It has one of the best looking displays I've ever seen as well.
That said, Steam Deck is still my main go to, because at the end of the day it is a full fledged PC.
I got a set of grips for it, but I'm not going to use them unless I'm playing a game using the analog sticks. That's the only part that's uncomfortable for me. On dpad-centric games I'm finding it very comfortable on it's own. Also just want to add that it has probably one of the best dpads I've ever used. Very accurate inputs, and just the right amount of tactile feedback without being quite as loud as the Xbox controller.