Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.

Q: As a student of jiujitsu i understood alot of the moves but i found that without previous knowledge these pictures and instructions were difficult to understand. I feel there is alot of good information but not worth buying.

A: Negative
****
Q: Good quality overall. The braket for the stem didn't fit my application, so I improvised, and mounted it behind the seat over the rear fender and low. Holds stuff.

A: Positive
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Q: This disc proves that there's much more to the Campbell/Webb association than the 4 or 5 hits from the late 60s we all know and love. 'The Moon's A Harsh Mistress', 'Highwayman', 'Lightning in a Bottle' and 'If These Walls Could Speak' are particularly fine Webb songs and they're given superb renditions by Campbell. The chemistry has always been right between these two and I hope it's not the last we hear of them together.

A:
Positive
****