Well, I got my new Honda tensioners (3) today (2/23/16) from South Sound Honda, and immediately went to compare them to the aftermarket one I bought last Fall from PartsNmore. Pictures below. To be honest, I cannot find ANY differences between them. The fit and finish appears identical, the rubber deflects the very same under the same applied pressure (8 pound weight, a big brick), whether pressed in from the side, pressed against the face of the roller, or twisted (by hand, this test). The holes are identical, within a couple thousandths of each other which I would expect from punched-out metal parts like these.
The only difference I can see between them is: their packaging. The Honda ones come in thicker plastic bags with their characteristic red part number labels while the aftermarket ones come in padded-cell plastic bags, with grease applied on the large roller's bearing (the Honda unit is dry). The slider tensioner is exactly the same part, from all I can tell. Even the little dimples of the rubber mold(s) are identical, except the aftermarket upper roller's dimples are slightly shallower, probably indicating the mold was a different temperature when this one was made.
I am wondering now if the vendor who made the aftermarket part(s) that PeWe got in 2012 was formerly making lesser parts, and recently changed them, or if Honda is using the same parts? Don't know...but I do know that it takes about 10k miles to make these rollers hard, based on experience with these engines, and after that time the rubber starts making tiny chunks out of the upper roller, which usually show up trapped in the oil pump's screen. These are hard as plastic by then, too. I also know from experience that the lower roller will get nicks and chips in it if the cam chain is run very loose for a long time, slapping it at hiway RPM speeds on a steady basis. But, I have never seen one fail, like PeWe's unit did?