I've used the HF blades with mixed success. Some are sharp and stay that way for quite some time and some are duds right out of the package. I prefer 60mm blades, so have purchased from E-Bay:
http://www.ebay.com/itm/231230080631...%3AMEBIDX%3AIT
The same seller also has the 45mm blades for a good price. So far I've only used one of the blades, but it seems to be holding up well. And when it gets dull I'll use the TueCut sharpener I have to extend the life.