hello!
i have used pro-mark graphics for the sport jets that i built. they are transfer~like and very well impresed and easy to use. if you go to a more scale approach, you can make your own art and send to them to be custom made. as i live in brazil i donīt have that faccility, so i custom make my own decals by the water slide method, but this is very difficult and you canīt have anything white and clear colors donīt show up over dark painting schemes. anything i can help, just ask.!!
one more thing, i use as samples to my decals plastic models decal sheets, from 1/48 scale.