Seeing how the factory insole in a Full Tilt is basically a piece of cardboard with some fabric on top a custom footbed will go a long way to making your boots more comfortable.
Once you've got the footbed you'll have to re-cook the liners as the whole relationship of your foot to the boot will change with a footbed.
As above, make sure the guy fitting them does it with a toe cap and I'm about 80% sure you're supposed to do at least the first part in a standing, slightly flexed position so the liner is the same shape it will be when you ski.
Go elsewhere, never go back. WTF. My old flatmate has a pair of Dropkicks with footbeds, that (shock horror) he has cooked twice.
Somehow they don't know what they're talking about.