Instruct: Classify a given review as either positive or negative.
Query: disappointing gadget!

ADVICE: DON'T buy this thing!I bought this thing hoping that it would really "navigate". It is definitely disappoining. I followed the instructions on the manual and calibrated it. It eventually got the right direction after several frustating calibration. The second day, it was totally off (indicating "N" while I was traving south). And now I just cannot get it work -- it is displaying "E" no matter where you are heanding, and no matter how you calibrate it.