Calbs,
The 9'3 will be a large step from your mana but if you are willing to give it some time and effort it will reward you in the type of surf you want it for. IMHO this is a far better option than a short board on the wrong side of 30".
the things to be careful of are:
1. the 9'3 runs a early large amount of rocker, so its not that fast to paddle into a wave, but this is one of the things that makes it work so well on a wave.
2. the deck is fairly rounded so your "sweet spot" on the deck will be smaller than the actual deck, this coupled with the thinner width will make it far less stable than your mana.
3. the rails on this board are pretty thin, again awesome when they are biting into a wave face, but not as stable as the thicker rails on some short boards produced since then which are designed to make narrower boards more stable.
that being said these are all the things that make this board perform in proper surf, which is where the wider short boards will suffer. As long as you are the kind of person who takes to things like a dog to a bone, then my advice would be to grab this board at a good price and hang with it until you get it humming.

THANKS GUYS FOR FEED BACK WILL DEMO BEFORE DECIDE CHEERS CALBS