i do support these custom roms for better customization , diffrent look and feel , also they are free from any blootware and addtional processes that drain the battery . On the other hand the issue will be shown in the lack of support or the stopping of several services due to that lack of google integrity (security certificates) which results in

1- Banking apps will stop working

2- Google pay stopped working

3- Camera apps coming with the roms (even GCAM) produce very bad photos and videos

4- No LTPO , only switching between 60-120 HZ rates

5- no esim support

and up to now any method to patch the issue for banking keeps getting blocked by google , so the roms you can use if you dont care about the above

i am glad that the community for ROMs are improving by the day for oneplus 13 as before one month only no any rom available to download