Yes remove them prior to having the wheels done.

Spending more than $100 on those wheels is subjective. A rubberized coating that is cleared will not get him the result that he is looking for. I assume (from his posts) that he wants his car (mainly wheels) to look good longer than a few weeks. Clear coating plastidip the cheap way will look like $hit in no time. If you want a proper clear coat (which you wont find a reputable painter that will clear coat rubber) it's going to cost 1/2 of the cost of powder coating. So add the cost of the plasti-dip, clear coat, and time (because my time is actually valuable) you are within what $10 of a proper powder coating job.
I am not anti plasti-dip by any means. If you want to use it more power to you for doing it yourself and coating something in textured rubber. But if you are looking for a quality looking coating for a car, spend the money to do it right.

Black wheels + salt?

Come on, anyone who's ever lived up north knows salt looks like **** on anything, but especially black.

I'd leave them, they'll look much cleaner longer if left unpainted.

Edit: The plastidipped wheels don't look half bad, if that's what the pics signify (can't tell, as the top pics looks much less of a deep black, but that could be reflection from the road itself). Also, with black rims, it makes unshined tires stand out and look bad. Get some foam or something on them! You paint/dip em, you have much more upkeep now.

dam nice parking brah any closer to that cement block hahaha...but the black rims look nice is tht PC or plastidip?

lol thats not my parking man, I was parked outside of a shop. And hell no that **** ain't plastidipped or w/e you call it. Got em sandblasted & PC'd for $350. And ya I know salt makes everything especially black look like ****. But I wash my car like once a week during winter so I don't care.

You can't go wrong with powder coat I'm getting my 18s oem wheels powder coated black n red rings my car is LR I got a deal for $43 a wheel...

$43 a wheel??? Damn you better hope thats legit powdercoating.

Oh yeah the guy's place is pretty legit he said $60 at first but he gave me a deal for 2 cars my G n my boy's 09 C class...I have to leave my car there for 3 days tho

That's awesome man. Ya I wouldn't have been able to leave my car for 3 days. I got lucky cuz my buddy had his stock wheels sitting around so I just threw those on.

Yeah that's what I'm worried about I work 5 days a week and sometimes I get called in the most I can leave it there is 2 days I'm probably gonna drive my dads highlander lol