Well it's a huge improvement over the original Cuttermaster too. I had one, the older version with the aluminum sleeved air spindle, which was worn and would constantly bind from carbide dust being dragged back into the bore. No air pressure setting seemed to prevent that. And the bore had plenty of scars the first time I took it apart, which helped explain why I got it for $300. Cuttermaster wanted nearly a grand for a new unit, I ended up making a new sleeve out of bronze. That was a bit of a project...
Anyway, the old Cuttermaster radius attachment, at least on mine, suffered a severe lack of rigidity, it required a fine touch to generate any radius or taper without it wobbling around. Since I was doing a lot more of that sort of thing than sharpening end mills, I sold it and bought a Deckel SO.
If I weren't stocking most of my new end mills off ebay cheap, I'd almost consider buying this new design, though I could probably find a serviceable full on cutter grinder for less.
All in all Iv'e had pretty good luck with the Darex air bar--although at one point a couple of the orifices had gotten clogged and so it started acting all sticky and weird...after much screwing around and head scratching thinking I finally ended up filling them in with solder then re-drilled using a tiny drill in a pin vise...good as new..
I'm of the opinion that I was swindled when I purchased the darex radius attachment--the POS it is so sloppy and the design so ill concieved as to make it all but un-usable for the intended task.
I would probly get a cincy #2 or maybe a ko lee for here but the floor space here is just plain too precious.
Mostly Mcmaster-Carr here, their end mills are generally name brand USA made stuff and while they're not top of the line they typically work out just fine for general purpose application....I might go someplace else but since we buy a gazillion other things like raw materials fasteners dowell pins etc from them anyways and frankly my cutting tool budget rarely exceeds a few hundred dollars per year so might as well have them toss in a handfull of end mill and save on some shipping.
I have a darex...works great for grinding the OD but that's about all--dish angle on grinding the ends is insufficient as it is and to make matters worse, the slide is permanently set to an angle that is so close to the built in angle that the diamond and borazon wheels drag on the finished work--and keeping an alox wheel properly dressed for that function is near to impossible as eventually you need to dress the whole side angle...
I guess so what Im saying here is that the two axis swivel design on the wheelhead of the cuttermaster would in my opinion be a huge improvement over the Darex at the very least.