Better than a blade and lets you grind your beans at home.
Positive Product Points
Simple, inexpensive, good starting point
Negative Product Points
Dust, static cling, fine grinds stick into corner of recepticle
Detailed Commentary
I purchased a KM 20 off eBay for a grand total of 21 bucks and it worked better than anything I owned before (this is my first). I found my second KM 20 at a garage sale for 5 bucks. Totally worth the price. I did notice that the grind of some beans was just not fine enough so I cut off the stop for adjusting the grind and now I can make it as fine as I want. I did notice that the grind is not consistant but it is better than any blade. I also had it plug up once but the unit is simple to clean and was easily fixed. The unit (KM 20) is sturdy enough that it has survived years of use and is still working fine, although I am surprised it was unmodified until I got them.
Buying Experience
eBay costs more (of course) but the garage sale deal is hard to beat