I got a C4 ISUP late last year. Its been from Sydney to Melbourne, Malaysia and Singapore. Have to pump it up way hard (approx 20psi, the guage doesnt go that high) or feels "bendy" in the water (although I weight about 95-100kg). Goes fine on flat water, which is what I wanted it mainly for. I've also used it with kids/mates etc on the harbour here and a good beginners board as pretty indestructable. I've only tried it in surf a couple of times, and frankly dont think I had enough air in it, the waves seemed to banana-bend it in the middle rather than push forward..... may also have been my technique. Havent gotten around to trying again since I got my new Icon in March. Overall would have to say I've been pretty happy with it. In hindsight I'd go for a shorter 10' model rather than the 10'6 XL I have but anyhow.

www.seabreeze.com.au/forums/Stand-Up-Paddle/SUP/Help-with-inflatable-SUPs/

there are some pics of it on the Yarra outing with DJ on my profile page.