Hi James
I've ridden both boards and they are great but obviously very different beasts. I'm 70kg and been supping for 8 months (I get out very often). The Oxbow is classic longboard style with lots of glide and a really great board for smaller days and flatwater.
The PSH is what I currently ride and I am totally stoked with the way it goes. It has fairly flat rocker so it glides really well for its length and can be surfed longboard style, noserides like a dream, but the big payoff is that this board is loose and light and you can really throw it about, hit the lip, snap back etc...
The PSH will take longer to feel stable on, but if you like your surfing you will probably want to come down in length and bulk from the Oxbow in a few months anyway. If you go the PSH get the new model with the molded in handle if you can as they are lighter.
Good luck with the decision - can't loose either way

! cheers Bill