I bought this a few months back and have hardly used it. If used while running, the movement of your arm causes the side volume key to be turned all the way down. I have tried multiple things: wearing it on my forearm as opposed to my upper arm, not tightening it as much, etc. and have finally resorted to just carrying it during running (which pretty much defeats the purpose). If used for walking, it usually works OK, but I definitely would not recommend this for running and high-movement related activities!!!
My dog (a 30 pound wire hair fox terrier and corgi mix) absolutely LOVES this toy!!! I originally got it so that he could have something to do while I was gone and he was in his crate, and was very disappointed to find that he pulled the circular rawhides off in a matter of minutes...at first I thought, "well there goes 10 bucks down the drain!". But after that, it became his FAVORITE bone. He just loves throwing it around and chewing on the bone ends. It lasted about 6 months before he chewed both ends off (note: he is a very very intense chewer), and even after that, he still loves playing with the purple ball that came in the middle. I bought him a new bone for christmas and again, he can't get enough of it. My roommates dog has the same feelings for these bones, and we have affectionately started calling them their "crack" bones because we don't know why they are completely obsessed with them! I would highly highly recommend!!!