Yea, listen to J-B. I have a Dremel brand with a Flex-Shaft and it is like working with a pencil. You can get into real tight corners and be very acurate with it. You really get alot more control with the flex-shaft.
Fiberglass reinforced cutting wheels (get lots) and sanding drums (get lots). I also got a nifty attachment that turns the dremel into a mini-skill saw. very handy and the blade is metal so it doesn't wear out like the cutting wheels.