Go with Spa For Cars. They use Menzerna products. But as you might already know, how deep your car shines, how long a swirl free finish on your paintwork can be maintained has more to do with skills than product.
In this aspect, I would say Spa for Cars would rank right among the top...
Just to get an idea of how detailed they are, here's a thread I made of their car washing process. You can see for yourself what kind of people and skills you will be dealing with:
http://www.bmw-sg.com/forums/exterio...many-pics.html
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