I badly wanted a KMG but couldnt afford to shell out that kind of money. I found somone selling home made ones based off of the KMG layout on ebay, he has since started selling them on his own website.
I bought one for $650 it came with a 1hp leeson motor and a digital variable speed drive. All i needed to do was mount it to a base and i was good to go. Ive made about 20 knives on it already and the only modification i made was to get a ceramic platten. This is his site:
http://www.2x72beltgrinder.com/Home.html
Im sure some of the big name sanders are superior, but for a total set up for less than half the cost of a bader(minus the motor) it i am very pleased with it