Instruct: Classify Amazon reviews into positive or negative sentiment
Query: the pump is great

I bought a Coleman 4 in 1 mattress, and wondered whether I needed the pump - after all, it cost almost as much as the mattresses (but was not expensive - right at $20.) Asked my daughter, and she said "yes! you'll melt part of the mattress if you try using a blowdryer, and it's just worth it". She was right - it didn't cost much, but I was concerned about storage space.It is not very large, so storing it is not a big issue. It quickly inflated my mattresses (I think it was under 2 minutes - but didn't actually use a timer), and is great for deflating, also.So if you're wondering if you really need it, I'd say yes.