Gil, don't know about the other stuff, but I've been running the same Sears version of the Dremel for about (25) yrs. with no problems. I use it at least 2-3 times a week doing everything from modeling, to cutting sheet rock- ceramics- grout- buffing /polishing, plumbing, and a number of times cutting auto exhaust pipe in hard to access areas, gaulded nuts/bolts, etc. It has been used and abused, but still keeps on going. The new ones may not be as good, but what is now, with everything made in China, Mexico, etc.
Doug