Buy the frame you want, then get the stuff you want on it. Nine times out of ten, if you buy a complete bike there's gonna be something on it you either don't like or doesn't fit etc., and you'll spend time and probably money to get it right.
When a shop builds a "special" bike usually the best and most senior mechaic or the owner builds it.
Get the BEST stuff you can or you'll ALWAYS wish you had!

Ride what YOU want
Pat