I own the previous iteration of this device which is now available for $50. I was so happy with the previous generation that I bought one for my brother and his wife for Christmas. The 1stGen product is great. For anyone who works out and hates headphone cables, it provides hours of music with reasonably thought-out controls.
When I saw that Sony had come out with a new and improved version, I had to have it. So far I have been impressed. Though the earpieces are fatter, they don't jiggle around at all, even when I shake my head hard. This is not really that important if you wear the device while cycling or rowing or anything else low impact, but I expect it will be a very helpful for running and boxing. I haven't taken it for a test run, but I expect excellent results based on initial fit.
Compared to the 1stGen, the fatter earpiece profile makes it look less like you are wearing two bluetooths when you work out, which is nice, and the band seems to be a little more secure. The controls are different as well: The old play/pause/forward skip/backward skip/zappin button is replaced by separate play and skip buttons on the right earpiece, and volume shuffle control on the left.
Only gripe: 1stGen used standard mini USB, meaning I could charge it with any of my cables that work with multiple devices. This one uses some kind of wierdly-shaped mini-usbesqe plug. Not convenient! That is the only reason for 4 stars. Otherwise a solid upgrade, and a great product. If you liked the old one, you will like this one even more.