I'll use this opportunity to get up on one of my favorite soapboxes one more time.
Dremel Moto-Tools are fine, well-made pieces of machinery. But for model building THE DANGED THINGS TURN TOO FAST.
Even at the slowest setting, the typical Dremel tool will melt styrene or burn wood if you're trying to drill a hole with a #60 to #89 bit. (You may get away with it if the bit is brand new, but when it gets a little dull - but with plenty of use left in it - you'll have to switch to a pin vise.)
For model building, I want a rotary tool that can be set on zero, while I put the bit exactly where I want it, and then ramp up the speed till it gets to a few hundred rpm. Same goes for delicate sanding and grinding.
Whenever Dremel puts a new one on the market, the advertising emphasises the power of it. But the truth is that scarcely any jobs in model building require particularly high torque, or speeds like 3500 rpm.
Dremel's website has a customer forum. I once posted a comment that I'd pay good money for a small rotary tool with speeds adjustable from 0 to 1,000 rpm. Nobody responded. So I guess I'm in the minority.
Dremel used to make a "tabletop speed controller" that set the rpm anywhere from 0 to the maximum speed of the tool. But that gadget has been off the market for years.
I like We-cheer tools too. (Unadvertised but noteworthy fact: they take Dremel collets. At least mine does.) I have one that I bought from Woodcraft quite a few years ago. It has no built-in speed control. (The current versions have the same sort of too-fast adjustments that Dremel's do.) I also have a Dremel 100 single-speed Moto-Tool. I rigged up a simple speed control of my own, using a plastic electrical box, a dimmer switch, a duplex outlet, two wire nuts, a length of electrical cord, and a strain relief - all available at Lowe's for a total of less than $15. I plug whichever rotary tool I'm using into the box, and away we go. It's not as nice as the old Dremel tabletop version (at very low speeds the motors stutter quite a bit), but at least it keeps me from setting fire to my models.
What this world needs is a cordless, rechargeable rotary tool about the size of a fat pencil, with reasonable torque and dial-in speeds from 0 to 1,000 rpm. I strongly suspect that such a tool could be made with today's technology - and I suspect that, if some firm like Tamiya or Micromark would make it, sales among modelers would be really good. I'd certainly be happy to pay $100 for such a thing.
Until that happy and unlikely day, I'll make do with my two old-fashioned tools and my little blue box with the two sockets and the knob on it. End of rant.