What he said...it's as much an art as a science, and you'll get a surprising variety of stories and experiences about it. It also helps if you know exactly what you're looking for, and what you liked or didn't like about the last boots you were in. I think that somebody also mentioned in this thread that there are two general aspects of boot fitting, comfort and alignment. Comfort, IMHO, is the most important. I ski in an Atomic RaceTech CS 130. I have two pairs, one brand new. I had the brand new pair ground once, then again, and now I can buckle them the way I want in the morning and ski in them all day without unbuckling. I also have them aligned the way I want, and alignment is obviously important, but if they ain't comfortable...fix that problem first.
So here's the story on my boots, and this is just one more data point for comparison. I have a pair of RaceTech CSs that have 130 days in them. The liners are definitely packing out, and the shells don't have any cracks or other problems, but I can feel them softening up. So those are my free ski/cold day boots, and I just got another pair of CS 103s. I've found that I don't do well with most custom insoles...they feel too rigid to me, and I can't feel what the ski is doing through the bottom of my foot. So I either go with the stock insoles, which in my new boots, seem just fine, or with a pair of Super Foot Blues. They give me all the support I need and the stance I want, and I can feel what's going on under my foot. The only stuff I needed to have done, comfortwise, on my old boots, was some grinding in the 6th toe area and on the opposite side, where the big toe joins to the foot. I went to my buddy Larry (Larry's, in Boulder) who looked at my old boots, looked at my feet, made similar grinds with some minor adjustments, and presto, they fit just fine.
I'm usually just fine doing cuff canting for alignment, and I dinked around with the cuff canting last year (Atomics let you cant both the inside and outside) until I got what I wanted...then I dialed the same numbers into my new boots, and presto...I feel like I'm lined up right where I want to be laterally. One of the reasons I switched to Atomics from Lange is that I don't need heel lifts, wedges between the liner and shell, or whatever...my basic stance out of the box is pretty much right on the numbers. The 130 flex is plenty enough for SL and GS, and I can ease the buckles back to soften the fore and aft flex sufficiently for powder, bumps...and SG and DH. Oh, yeah, I also added a World Cup Booster Strap, which I always do, because it makes the forward flex progressive.
So that's my story...your mileage may vary...

Quote:
Originally Posted by
SkiMangoJazz 
I have had bootfitting done a few times in my years of skiing. It is definitely worth doing. The results will vary widely as there is as much art as there is science to it, in my opinion. Let's just say that in spite of what a fitter would say, it's an inexact science.
That said, having your boots setup so when you stand in a natural athletic stance that you are balanced fore/aft and canted properly left to right is very important to developing skiing skills.
I have spent anywhere from a little to well over $200 which included a new footbed and extensive heating up and shaping out parts of the shell that squeezed my foot, and sole planing.