I was holding off on posting my review until I strung several more rackets but now is a good time as ever, I guess.
FYI: I have about 10 years of stringing experience through several shops and clubs I worked at prior to graduating college.
I recently purchased a Mutual Power Alpine 4000. I decided to go with Mutual Power because I did not want to spend the $$$$ on a Gamma, etc. I found very little feedback on Mutual Power, but the feedback I did find was all positive. So far I have strung about 10 rackets in the past 2 weeks since receiving the stringer. In the past I mainly strung on Ektelon Model H stringers. As for my thoughts, here you go: So far, so good. The clamps are very stable, hold the string very well and glide nicely. The crank-pull tensioner is exact and easy to use. The racket mounting on the Alpine is a bit more work then the Ektelon, mainly because you have to screw on the mounting posts that hold down the frame compared to the Ektelon where you just had to close the lever. The K-shaped pieces that push against the side of the frame for extra support work great. Overall, the mounting of the racket is easy and it definitely keeps the racket very stable during stringing, no movement at all. Once the racket is mounted you can also adjust the height of the entire upper unit that the racket is attached to. This I found to be very useful. If you have a racket with an 18mm side beam and then your next racket to string is a large widebody that has a 26mm side beam, you can adjust the height of the unit so that you can manuever the clamps much easier and also so that the clamps remain in more of an upright position depending on the size of the racket.
With my limited amount of time using this stringer I really can't comment on much more. Hopefully my experience thus far is a good sign for the future but if I do run into any problems, I will be sure to post them for everyone's reference, as well as posting any other of my findings.
-Erik