The problem is that the hedgehogs vary so much in quality there is almost no guaratee you'll get a good one.
I've seen several reviews of units purchased at stores, where the bottoms were very unsmooth/unpolished. Also, since the pins are SOLDERED onto the base, a handpicked "review" unit would easily outperform an alpha, since a stock one is on par with an alpha.
But that also means a "handpicked" hedgehog isn't going to be indicative of the average purchaseable hedgehog.
this is a very similiar case as to the Arcticooler that Kyle @ hardocp tested a while back. his had a nicely lapped/polished bottom, whereas the majority of shipping ones do not. As can be easily seen, a smoothly finished bottom of a heatsink is vital to cooling, hence why some purchased hedgehogs do perform rather unspectacularly.
Mike