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

[Q]: If you are not in really good shape this is a great product to get ready for P90X. It does get kind of boring because you are doing the same workouts every other day, but they do work. It is only about 30 mins but it is amazing how well it works.
[A]: Positive


[Q]: Product received timely. The plug in feature is favorable in that there is no concern of battery failure. Product is easy to use.
[A]: Positive


[Q]: I ordered these shoes to replace the previous pair that had ripped apart at the sole. Clark said they did not make this shoe anymore, so I had to order them through Amazon. Sadly, the second pair ripped in the same place within 3 months. My son has since bought a similar pair from Sperry and they seem to be holding up much better.
[A]:
Negative