Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Great ball!

I bought this med ball from Amazon about six months ago, and it hasn't deflated at all. Med balls in general are expensive, and when I priced them out, this one from Amazon seemed to be the cheapest one for a ten-pounder.It's about the size of a basketball, and has the same traction on it -- which is great when you're working out and have sweaty hands! It's easy to keep your grip on it.This is a really high quality product; I use it about once or twice a week for ab workouts, and it's in perfect condition. Highly recommended!UPDATE ON 3/2/11: I just wanted to say that I've had this ball now for over a year, and it hasn't deflated on me at all. It's in perfect condition, and has really held up well!