I need an advice

I´ve been watching this board as a classic one;

 

what do you think of this shape?

 

http://www.youtube.com/watch?v=wLB7EdxQy2E

go for it!  looks like a fun board

but she seems to be a "flat" rocker and I intend to ride sometimes from 7 to 10 feet high;

 

doesn´t she become a dificult board in a little bigger waves???

 

(for instance this one I´ve tried but she´s has´nt much floatability...http://www.youtube.com/watch?v=_-fiFz0g43o&feature=related)

you are answering your own questions, make adjustments that you feel will be right for the board in the waves you will ride it in....