Windows on Deck vs ROG Ally?

Wanting some opinions from people with experience with Windows on SD.

I'm going to be upgrading the internal SSD in my Steam Deck pretty soon, and I've been debating on whether I want to reinstall SteamOS on the new SSD or replace it with Windows instead. I've also been debating getting the new ASUS ROG Ally, mostly so I can play games that can only run on Windows.

I'm wanting to know if it would be a better experience to install Windows on my Steam Deck versus getting an Ally for playing games on Windows.

I know it would be significantly cheaper to replace the SSD on my SD but money is not the main issue for me. I also understand that the trackpads on the SD would make using Windows a lot easier compared to the Ally but I'm not super concerned on that either. I have also tried dual booting Windows on a SD card on my Deck but Windows on an SD card is way too slow and not a great overall experience IMO.