Summary: As a contractor and long-time woodworker, I have a lot of experience with tools. However, this was my first Festool, and after reading all the hype and on-line praise, I think I was pretty much expecting the sander to operate by itself while I just stood back and watched! It's a nice little sander all in all, but I really think there's more hype than substance in getting over 400 bucks for it.
Summary: Used this sander for about 2 weeks now on some jewelry box projects. Wow what a difference, the power, dust collection and long lasting sanding pads have been fantastic. This is the second Festool tool I have purchased the first being the 55req track saw, it's awesome also. What I like about this sander is the ability to go from very aggressive sanding to very delicate sanding just by changing the settings on this sander.
Summary: Probably like many other woodworkers out there, I felt Festool was overpriced when compared to similar products, so why should I pay that money just for the name? That all changed recently with the purchase of their "Domino" loose tenon machines (I own both) and now the RO 90DX sander and a companion dust extractor. Festool is a cut above many of their competitors, and there is a reason for that.
Summary: Yes, at first it seems as if this price of this tool is outrageous. I agree. But, it is worth every penny and more! I refinish wood floors for a living and I use it all the time. Fits is small spaces, easy to use, quick paper change, easy to control dust. It is very well built also. Aggressive speed is very strong and the more gentle speed leaves a very fine, swirl free finish. Please feel free to ask me any question if you like.