Depends on your use case really. If you are only into retro emulation up to PS2 and a little bit of PS3 and only play indie games than the deck is fine. If you play AAA games and new releases, ally all day. I've had deck since launch and I spent about as much time tinkering and getting things to run as I did actually playing things. So far with the ally everything just kind of works no tinkering.
AC works great, steam bpm gives a very deck like ux and ui, so this fictitious argument about a console-like experience only being available on the deck is bs.
I'm keeping my deck for when I need battery life, as of now deck performs better at lower wattage than the ally although not by much.
Ally has MUCH better screen, I prefer the feel of it's buttons as well.
And another thing, the 64gb price isn't what it's going to cost. You have to add storage, either SSD upgrade or micro SD, and shader cache is an issue for 64gb so you will eventually have to upgrade the SSD at a minimum to 512 which usually runs about a hundred bucks so that 400 ends up being closer to 500. For what, 200 more you get a massive performance uplift, even on early drivers it's double on some games, better range of TDP and performance options, much better screen, way better compatability, and the same ux if you want
I don't think I've ever used the track pads on the deck beyond desktop usage.