Dont go for cheaper options, i made that mistake. Loads of problems. Buy either Philips or Osram. Have you looked at your lights? can you see the ballasts? If so, this is the bulb you need!
Use Avery Supreme. I do this for a living. 3M are good but not a patch on Avery. You can order it from Spandex Uk.
https://shop.spandex.com/en_GB/product-catalogue/vehicle-wrap-protection-accessories/colour-change-vehicle-wrap-films/high-performance-vehicle-wrap-films/avery-supreme-wrapping-film/p/f10
If it were me id grab some and see how it goes, if there's still a problem then id take it to a recommended garage near your location and see what they say.
A little bit I guess, but not particularly. It does seem to be quite inconsistent, it doesn't get progressively better or worse, it's just... for lack of a better word... random
Did you try Molyslip?
Not sure where these prices are being obtained from, you can pick them up for £800 each from Nissan:
http://www.ebay.co.u...D-/291829834825
Or less from a parts supplier if you shop around.
That was for a pair if you add on the vat! Even without the vat or if thats £800 inc vat its still £1600.
Ive got 19'' LMGT4's, and like you say, I wouldnt go more than 15mm with wheel spacers. Arch rolling would be the next option but i'd rather not go there!