I went to Max Out Golf a while back and spent over $500 on the custom driver, and about as much on new shafts for my irons. I didn't see anywhere near the improvement I was told I'd see, and later found out that they recommended that driver/shaft combo to everyone, and the same iron shafts to everyone who came in. It became a running joke -- someone would see the shafts in my irons and would ask if I went to Max Out Golf and, if so, "let me guess, your driver is $model with $loft with $shaft in $flex. They told me that was optimal for me too!" So either there were a lot of people in the area with those specs, or it the fitting process they had us go through was a hoax.
I'm all for getting fitted, but get a company rep who wants their company's driver to be the best it can be for you do it. Try a few different companies' suggestions (and don't go for a fitting that'll charge you!) on a monitor and find out which one really is best.