Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Cheapest method so far

these balls really do work, I have used them off and on for various body parts. I struggle the most with my neck traps shoulder area. I find it take more time with these the first few days are still tight and sore then they start to loosen up. The problem is I stop using them and forget to do maintanence and I have to start back at ground zero.It is very relaxing and I shouldnt forget to do them every week but life is busy and it happens. Still the cheapest fix for my shoulders and I tried many things over he last 3 years