The Manta has been discontinued as of this year, basically because the Manta and Frenzy were getting so close to each other in performance that they
became redundant. In '09, the Manta was a bit higher performance over the Frenzy but was more twitchy. You had to drive it a bit harder to get it to
perform but when you did, it payed you back with some awesome performance. It is the ultimate in freestyle riding where the Frenzy was slightly more
tame and didn't require as much aggressiveness.
The '11 & new '12 Frenzy is an improvement over the '09 models and has just as much performance as the Manta did without having to get as
aggressive with it.
Hope that helps.