Great truing stand. Comes calibrated. The only annoying thing is that you'll have to buy a separate base for the stand as it will tip over during truing. Of course, Park sells a base but they really should just include the dang base and charge more for the combo. Anyhow, if you don't buy the base you'll have to anchor it down to your work bench with two bolts...and there are holes on the stand for that.
I like the tool as it allows one to much more easily true a wheel. However, the jaws used to gauge wheel trueness have to adjustedcentered to match the dishing of a given wheel with a wrench rather than a adjustment knob when a given wheel is not perfectly dished (and most usually aren't). Of course a wheel should be well dished but even a small dish variation requires a tedious adjustment of the stand to accommodate the variance. Note that the stand can be used to correct dishing but it usually takes much more time to correct a dish error than it does to simply true a wheel. For the (not inconsiderable) price of this stand, I think that Park should have included the centering knob of which I speak.