Lots of debate on what the best product is, truth is its all down to cost and the detailer carrying out the work for you.
I've found, having detailed a fair few cars, that synthetic coatings don't offer the same level of depth and shine that a quality carnauba wax like Victoria concours wax or Swissvax will. Upkeep on wax layers is more time consuming but if it's garage kept and you aren't on the motorway a lot I'd say that a wax would look the best on the car. I found that applying waxes by hand was rewarding and loved spending silly amounts of time detailing my old 8L S3 in the garage.
I opted for GTechniq Crystal Serum and EXO (called crystal serum black) as I wanted longevity of the coating and the scratch resistance it offered, GTechniq seemed the best in my opinion 7 year Guarantee on it and I must say that it's so far doing an excellent job of keeping the car clean with truly minimal effort, snow foam and G Wash is all I need.
The problem with this coating is that it's professional detailer applied only, so you cannot buy it and do it yourself. I had TI22 do mine and my Fathers A7. Well worth it.
Hope that helps.