And what exactly do you consider "a great experience"? Because in act 2, with the game looking as shit as it possibly can, it still struggles to stay above 20FPS. I haven't bothered trying act 3 on Deck, but act 3 is even more resource-intensive than act 2 so I can't imagine it fares any better. "A great experience" is admittedly subjective, so I can't say you haven't had what you consider to be a great experience on Deck, but vaguely describing it as "a great experience" is negligent at best and outright disingenuous at worst. My act 2 experience on Deck was abysmal, and I think most opinions on that level of performance would agree.

For those that don't care about Linux, or portability, or the steam deck being a PC, and just want to play BG3 on their TV for as cheap as possible, the Series S is by far the best option. That the game will also look and run significantly better than it does on steam deck is icing on the cake.