The binding check by a ski shop is not as much about adjustment as it is about verification and testing. Your bindings are likely adjusted near perfectly by Spruce (Jeff) but there is no way for Jeff to verify the settings without your boots. The ski shop will place your boots in your new bindings and measure the pressure required to twist/pull the boots out of the bindings. If the pressure is too high or too low then they may make adjustments. They will also test general operation of the binding. You can approximate the tests required for this verification but the ski shops have specialized tools for it.
As Bluewing mentions this is cheap, usually a $10-25 service if not free. My ski shop throws it in once with any preseason wax & tune. You just spent a couple of hundred bucks on a new set-up, spend the few bucks for the peace of mind to get them tested professionally.