Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Need More R & D

This is a great concept, when it works. I took it back after last Christmas & exchanged it 4-5 times within 4 months time, all quit. They need to work on Quality Control. This is a light that most mechanics or handy people would love! It is such cool a light - too bad it is not reliable. We so wanted one to work.