I'm pretty sure the pump in the PNSD0060DO2260 is a Pentair Dynamo pump (I remember looking at it a couple of years ago). I haven't looked up the GPM rating lately (don't remember right now which size Dynamo). But, as you say, the filters in the matched sets are always smaller than the recommendation in the Hydraulics 101 table. [edited to add: In this particular Pentair matched set, I think flow rate and filter are closer to being matched than in many other packaged systems out there.]
I believe there are significant flow differences between different pumps with the same apparent HP rating. Apparently there is no consistent meaning to the HP number (and there are terms thrown in such as 'up rated' and 'full rated' and 'service factor' which distort the HP numbers the manufacturers put on the units). If you take a look at the pump curve table [edited: I actually meant the "2 Speed Pump Flow Rates" table] for two-speed pumps (also near the top of the Hydraulics 101 thread - post #2 in the thread) you will see that flow rates vary quite a bit for supposedly the same HP.
I wish I could trust some of the cheaper dual speed pumps out there (like this Doheny one, for example), but information on them seems hard to come by. On a different issue, I don't think I would buy this particular pump, simply because of the digital control stuff built into it -- just one more thing to fail, on a pump from an unknown manufacturer, is how that looks to me.