Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Buy these NOT EX71, these are less expensive, have the same sound quality and LAST LONGER!

I bought the EX51s and used them every day for over 2 years. After that much use, the left side started going in and out, so I decided to replace them. Because of the great sound quality, and the durability, I wanted the same ones. When I searched Sony earbuds I found the EX71s, and they looked the same so I bought them. BIG MISTAKE, see my other reviews for the details on what's wrong with them. The EX51s are great, I was so happy when they came in the mail and had an appropriately long cord without that annoying heavy connector cable and the wire covering isn't sticky and weak like on the EX71s. The 51s cost less too! Buy these, they have great sound and after one day are already holding up better than the EX71s.