I've been playing with the Pro Open 2011 for two weeks now about 2hr sessions pretty much every other day and have not had any noticeable pains anywhere. Off center shots doesn't create any jarring that you would notice compared to a old school prostaff or the newer six.one (those are my only references to player type racquets). It has a fairly large sweet spot and the feel is amazing. Sorry I cannot compare it to the PD but I will say against a heavy hitter you would notice it does lack the heft.
Just my 2 cents.