I've got the plastic blade seven2 and I love it.  
I'm sure there's a performance difference from
the Carbon fiber blades, but not one that I can
really notice being a beginning playboater.  The
power is all there, the grips are grippy, and the 
subtle bent shaft is already helping my shoulder
strain.  I'm not sure what happened with Boris'
paddle, I've used mine about 5 days and no
problems, with some good hard surfing too.  The
reports of breakage make me nervous, but I'm
gonna just keeping paddling.