You can still have the lip polished if you powdercoat. It's actually a process similar to painting, just that you spray on a powder (instead of a paint) and then "cook" it.
Powdercoating is generally more durable than paint; I haven't had powdercoated stuff in the sun enough to know how badly it fades with UV exposure

. I'd *guess* that it's not gonna be a big issue (or at least not more so than paint).
But paint is easier to touch up and getting currently-painted/cleared wheels
repainted will often be easier than getting them powdercoated (less prep required).
If you have a good, local powdercoating shop I'd at least talk to them- it would be a good way to go. If you have a good relationship with a paint/body shop, that might be the simpler way. I'd make the call depending on what's locally available (with a good reputation).