i mean it is called "post market os", and yeah hardware driver support isn't that good unless you get a community supported device. my one doesn't have camera, cellular, gps, etc.
Luckily my phone is pretty well supported out of the testing section though, so it has wifi and (partially broken) 3d acceleration
Mine is a budget phone so the performance is not optimal, but it's still fun to play around with.
I don't think the phones being old matter that much though, I haven't had too much performance issues (except my browser that doesn't have 3d acceleration working)
glorbo