Both are great, as is Fedora, the one that both are based on.

Nobara had some issues updating correctly for me, but I haven’t seen anyone else express that, so I don’t think it’s a common thing.

Bazzite is really gaming focused, so it’s harder to do general purpose computing on it than a desktop OS.

But they are both great OSes, and really you should just try out a bunch of them and pick the one you like the most. They’re free after all.