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

I've owned this CD for a few years, yet thought something was slightly off, so I compared "Keep A Knockin" to another copy I have.Results:Original is 168 beats per minutes, while this version is 172 beats per minute.Original's time is 2 min. 23 seconds; this version is 2:16 min.
Negative

Who would buy it not knowing what is on it, is there any new material, is there a better version of music than previously released, how many, etc., etc. You've got to tell us something - give us a reason to buy it - give us a few short pieces to listen too! King indeed; he's pretty good but the King has been dead awhile (notwithstanding the occasional phantom sighting) and the remaining living creators of original rock and roll - Jerry Lee Lewis and Chuck Berry are very much alive and touring and in Jerry Lee's case still recording great music.I'll take a look at buying this if I can see and hear what it is!Jimp.s. sorry for the 1 star but ...
Negative

This DVD is one of my all time favorite musical DVDs. Miss Jackson proves why she is the highest paid singer in the industry. With a combination of costume changes, great choreography, Janet's greatest hits, and a sold out crowd at Madison Square Garden, the DVD makes for an excellent night of entertainment. I only regret that I was not able to see the concert in person here in my home town due to a cancelation of the concert;however, the DVD is definately a suitable substitute. I highly recommend this DVD to any fans of Janet, lovers of music, and owners of quality DVDs.

Positive