I have flashed my Mi 11 Pro and have been using it since Monday. The flashing process was quick and easy and I faced no issues changing from stock MIUI rom to Xiaomi.eu rom.
For me personally, I am not experiencing any bugs but if you check the Mi 11 forum you can see if any of the bugs will affect you. I don't use NFC for payments but I do use it for NFC tags and it is working normally. My banking app is working and Google services too.
Battery life is okay but I think mine is draining faster because I use 120hz and WQHD+ all the time.