Just my thoughts.
1) Use whichever you find the most enjoyable, and whichever you think looks the best. They are all fine products. Keep in mind glazes alone don't offer very much protection, but maybe you don't really need any.
2) You can use dental floss and a hair dryer to soften and cut the foam. Then use the hair dryer and some 3M Adhesive, Wax, and Tar Remover to soften the adhesive. It should roll off carefully with your fingers (don't use your nail as it may scratch).
And a suggestion. If you want to just wash with water, I'd suggest using this instead. Any time you are washing, it's for a reason. So whatever you are washing off has the potential to scratch. Car wash makes the water slicker and better lubricated to help prevent scratches:
http://www.protectall.com/qelg.htm