Thanks for all of the tips, guys.
I ended up buying a Taig 2018CR-ER from Andrew at
www.computersculpture.com. It seemed my best bet for high resolution and for milling the tiny stuff I need. Besides, the upgraded spindle runs at 10000 RPM - which will be great start as I learn the intricacies of high(er)-speed aluminum milling.
If the 10K spindle won't cut it, I'll try an even higher-speed spindle. Since I'm milling with a 1/32" cutter on my finishing pass, and using a .00625 stepover for a smooth finish, I'd like to get more than 7 IPM when I'm cutting. Maybe 60,000 RPMs will be the way to go. Zing!
Truth be told, I picked the Taig after realizing that there was no way my wife would allow the Super X3 beast into our small garage!
BTW - Andrew from even called *me* to be sure my machine choice matched my needs, and he was helpful in recommending collet selection and material selection for my application. He really knows his products and I wouldn't hesitate to recommend him to anyone "on the fence" about machine selection.
---Will