Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Best backpack straps ever

This is for the Protec musical instrument cases, Very ergonomic and comfortable. Has a sternum strap (in case you are planning on rappelling down any mountains or skydiving with your violin. I personally don't use it riding my bike around town, but good to know it's there if I need it). The only downside is the system of attaching to the case is not real handy if you want to take the straps on and off a lot. I suppose you might get accustomed to the routine, and there is a pocket on the back that they are designed to fold up and go into. I personally just leave them on all the time. My shoulders are a lot happier since I got these straps and the Protec case. Oh yes, one other thing. Unlike some other cases, this system keeps the case from hitting my bike helmet.