Steam Deck, ~3 month review.
Disclaimer: I have never owned or used a console other than borrowing my partner's Nintendo Switch. Almost everything I know about consoles is second hand. I'm a Linux gamer and fully ditched Windows a couple of years ago.
TL;DR: this is arguably the best gaming experience I've had, with the exception that translating mouse+keyboard to controller is still challenging for me and I'm being a little conservative about game choice.
My Steam Deck has bumped up my gaming time by a significant amount and I have a new appreciation for Steam Input after not quite getting it with my Steam Controller.
It's portable in way that a Laptop simply isn't: this is something I could play on a plane or a train or a tram. I've already travelled overseas with it and while I didn't pull it out on the plane, I so easily could have. I did make a lot of use of it in hotel rooms.
I remember Linux gaming at the beginning when drivers sucked, but a few games got ported, then UT2004 launched with a Linux installer on the retail CDs. I remember the promise of Valve embracing Linux with Steam Machines and that effort faltering, then being reborn with Proton. The Steam Deck feels like the culmination of all of this and makes me feel like we could be close to the year of gaming on Linux. In all honesty, handhelds running Windows seem silly in comparison to the "perfection" of Steam OS on the Steam Deck. It feels like Windows has been leapfrogged in the retail space.
As for Steam OS and the tweaked version of Steam it runs: "hacking" isn't: you're in a walled garden which is less "walled garden" and more "nearly endless forest" and if you want to leave, well the option's right there on the power menu with the only caveat being you need to run Steam to get a keyboard and touchpad mouse in the desktop environment. Want to install an alternate Proton version: just do it from the desktop environment. Dev mode: just enable the toggle in settings.
It is very much "just a weird laptop" in that there's nothing really stopping you from just changing stuff in it. Parts and repair guides are available from iFixit, alternate parts (e.g. hall effect joysticks, expanded storage) are readily available and installing an alternate OS is no more complicated than on a PC.
It's very polished in a way that we've come to expect from Valve and is also a powerful and flexible gaming machine and shows off the flexibility of Linux. I'm very happy with my purchase.