JKnight is correct. Everyone who keeps an exceptionally clean car has their own recipe for doing so. Me personally, I go with the Meguiars over the counter stuff because it's cheap, it's on every store's shelf, and the end result is just as good as the expensive online stuff.
However, like most products we use on our cars, the devil's in the details. While I've never used Zaino before (read above comment about prefering cheap), I have read countless times that Zaino wax will last 6 months or better, even in harsh conditions. Everyone I've ever known that's used it was satisified, even with the high cost. So I'm guessing it's as good as all the hype. So if you're not a "have to clean the car everyday" kinda guy, then Zaino is probably for you.
Someone mentioned using a quick detailer spray before applying magnetic numbers. This is also something I do (and recommend). I've used Meguiars brand "Mist & Wipe" detail spray for 10 years until last year. When I picked up carcaresuperstore.com as sponsor, they turned me on to this stuff...
http://www.carcaresuperstore.com/index.php...products_id=199 I'll never use the Mequiars detail spray again. That Prolong stuff is awesome. The Mequiars spray is a thin, clear liquid, with some perfume in it, that has a bad habbit of hazing. The Prolong is a thicker, milky liquid, with a citris smell, that easily wipes away and never hazes. 5-10 minutes of wiping down a car with Prolong and a microfiber cloth, at the paint glows like it was just waxed. No lie, I barely wax my car once a year, and water won't stand on it. Keep in mind, it's also a car that's garage kept, stored winters, and seldom sees rain. For those reasons, I don't need to wash it much. Just dust it off from time to time. Excessive washing will also kill a wax job pretty quick.
My recipe is as follows:
Clay bar- Mequiars or Mothers are good/cheap/easy to find. This will remove tar/bugs/other contaminents.
Cleaner wax- I prefer Mequiars Medallion paint cleaner. Not so easy to find anymore, but works better than anything I've ever used to strip off old wax , which is where most of the dirt/contaminents are hiding.
Wax- I always been satisfied with Meguiars Gold Class, and the newer NXT stuff is pretty good too.
Detail Spray- Prolong, for all the reasons I already mentioned. Pretty much whenever the car is dusty I do this. After it sits for awile, before autocross events, after autocross events, ect.
And my top secret home remedy to remove cone marks (drum roll)......................................WD-40.

Seriously.