I think you need as good a base for your final product as possible. Start with a clean page! I would read the "Lee's Detailing FAQ" article under the DIY tab at the top of the page, and either do the wash/clay/de-swirl/polish/wax myself, or have a pro shop do it. Once the surface has lost all the problems you describe, then you can do tha Zainos, Mequiars, 3M, or whatever floats your boat. But the foundation is the most important thing, IMHO.

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E