The golfclubreview site seems to be pretty good in unbiased equipment reviews and they pretty much highly recommend spin balancing balls. If you scroll down it has a specific review of the Technasonic Check-Go device.
Is it going to make a hacker into a scratch golfer....no, but it looks like it could save a couple of strokes per round both in a little longer and straighter tee shots and in putts that roll true. I am going to pick 1 up cause for $25 it seems like a no-brainer to get something that can help your good shots become even better.