I have used the Supercut in the past, but opted for the Multimaster. I think that many of the advantages of the Supercut went away when the Multimaster went to the Star-shaped blades.
The Supercut is definitely a more powerful machine, but maybe too much so. The new Multimasters do a great job of harnessing and balancing the provided power.
Unlike some of the other posters, I do use mine for sanding and it does the job well. Well enough that I gave my PC detail sander to a friend.
As others have posted, the Multimaster is really a "swiss army knife" tool.
- The scraper attachment works better than the LS130.
- The ability to cut grout lines is second to none. In the past I have used either a grinder, Dremel, or worm-drive saw with a masonry blade. The difference is carpet-bombing to tactical precision. Even compared to the Dremel, the Fein is easy to handle and put in the right place.
- The sanding capabilities are good, and dust collection is acceptable.
- Lastly, and probably most frequently, I use my Multimaster to replace a jamb saw. In the past, I have used a Crain setup, as well as numerous handsaws. Never again.
I am excited to see how the new options from Bosch, Dremel, and Rockwell are received. I will purchase one of these for my father for Christmas, but haven't decided which.