i've got a little space, and i had mine heat molded too.  i haven't got any shinbang, or any boot problems at all so far this year.  full tilts really are ill.  i think i have a space just because i've got skinny legs.  if you do too thats probably why.
and i love how whenever there is a boot related question everyone just yells out 'go to a boot fitter!!' 'get the boots that fit you!'  haha its like we all just put a blind fold on, got piss drunk and walked into a ski swap and grabbed the first pair we could find in our blind, drunken stumble.
but a fitter really does help