I don't play my Deck a lot since I do most of my gaming on my desktop (also Linux). However, I think the Deck is a great device, and I'm glad these handheld PCs are catching on.
Although, none of these Deck competitors (that I've seen anyway) get the small things that the Deck did right. Where are the trackpads for navigating the desktop? Deck has four back buttons, some of these competitors just have two. Deck has a symmetrical stick layout like PlayStation (WHY don't more controllers do this?!), most of the competitors use the typical asymmetrical layout. I think the Deck is super comfortable to hold and play on.
Playing on Deck has unexpectedly made me retroactively appreciate my PSP more. One day I was playing it and realized, "Oh, you know this feels like a bigger PSP". I didn't like it as much as the DS at the time, but the PSP was a very comfortable handheld to play on. And you appreciate the bigger, wider screen the older you get. I didn't think much of it at the time, but getting a console-like experience on the PSP back in the day was quite an achievement. Now, with the Deck, I can literally play Valkyria Chronicles, or Persona 3: Reload, or Half-Life 2 in bed or on the toilet.