By all means wax them. What you should not do is machine polish them or use any polish on them. I just replaced bonnet stripes, laminated, and added boot strips and waxed the heck out of them straight away, 4 coats of carnuba. They glisten in the noon day sun.

 

I wax mine all the time, weather its from the carwash soap I use with a little wax in it or when I wax it by hand every three months. It looks brand new like the day they put them on. when I see customers MINIs at work some have really bad scratches or swirl marks. Mine have none. Or I see the occasional cracked ones.

 

Bought mine used and my stripes (white) looked exactly like yours when I bought it. I tried several things with no luck. Then, I used Meguiars PlastX headlight cleaner on them - very gently. They look like new. I waxed them up and they look great. They will have to be replaced at some point because part of the finish has been removed, but they are nice and white for now.

One word of warning - if you do this, keep it off of the paint. Tape or whatever around the stripes.

Good luck with the warranty.