I bought my Cardio Canine early in 2007 and am very happy to give it my strongest endorsement.  As an engineer, I'm quite particular about product-design in many things that I buy.  And I'm extremely impressed with how this product is both designed and manufactured.  A lot more thought obviously went into it than most people would ever expect from a pet product....and it all translates into a user-friendly product which is made to last a long, long time. It's been quite a while since I've been as impressed with a purchase; this one simply exceeded my expectations. I was tempted to buy a cheaper product but am very glad I chose the cardio canine. I would recommend the cardio canine without reservation (PS....I initially ordered the wrong size and the exchange process was completely hassle-free and prompt).