Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Spotty at best

I have been using Verbatim Lightscribe disk for about a year with no problems at all. Unfortunatly that is not the case with this batch. Every disk fails when burning to them unless I burn at 4X speed or slower. When at 4X I only had about a 50% fail rate. I had purchased a total of 60 disk and had over 40 fail.