As they are like transfers,they are close to the same thickness as the original paint - Definately less obvious than the Stick on decals.
Sinbad - you need a flash apron in the flesh to scan it -in sections if you only have a A4 scanner as I have.
I realise its not original paint but it looks great and isnt obvious unless you look closely as well you will never match the original colours.
Maybe I can describe fully how I did it in the new Tech Learning Thread ?
Millsy

Millsy if I scanned mine you make me some decals? Someone has touched-up some of the artwork on it, and it looks shitty. It has some rust stains as well.