Just my opinion but it looks like you could use just a touch more air in that tire judging by the heavy wear just outside the inner compound. Not a lot but maybe 2 PSI more than you have been using. Otherwise it does not look all that bad to me other than maybe somewhat short on mileage. The PR3 is a relatively new tire though and I don't think we really have a good idea yet how long they will last compared with other tires with better known characteristics. It is normal for tires to wear with a slight 'scallop' around the leading and trailing edges of the tread blocks.
By all means, try a different tire though. There seem to be a bunch available to choose from at the moment, which is all great news for us riders.
I am tempted to try a set of Continental Road Attack 2's occasionally but Michelin PR2s have performed so well for me that I always hesitate to move away from them. I did try a set of Pirelli Angels with OK results but prefer the Michelins.
As far as the visual look of the tire, I would not worry about any slight imperfections in tire wear as long as you cannot feel the defect when you ride the bike. Truly scalloped tires will absolutely get your attention.
Brian
Sorry I didn't post last night. I'm not sure if you'll even see the scalloping as it's in the early stages, but here a few shots. I met a few friends yesterday and one of them immediately mentioned it to me before I even noticed.
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