Hey Timo, You are correct in your assessment of two-stage verses single-stage and the more clear coats applied the deeper the look,but the thicker the clear the greater the chance of chipping.I tend to use a two-stage system on a custom,show or at the cutomers request.When I am going for a original look I personally like to use a single-stage system,PPG's Deltron works quite nicely for me but I would find a quality shop and trust them to recommend the brand, painters usually have a system that there comfortable with, I would not want someone learning a new brand on my car as some paints are thick some thin and you want a painter who is tuned in to that brand. Well thats my $.02 on paint selection hope this helps

Clayman