I've had 12 years experience as a CNC vertical machining center programmer/operator, and 8 years as a CMM technician. In my opinion, there is no substitute for the abilities of a CMM (with decent software), but I've also learned not to put too much trust in a machine. Height gages, indicators, and gage pins (in the hands of the right people) are great tools for testing and verifying the accuracy of a CMM. Anyone who has ever had a machinist or toolmaker prove their CMM results wrong with a simple height gage will know what I mean.