Dude, you'll be up and going in no time, so buoyancy wont be your decision factor. Get the Impact vest (not as much flotation as PFD) if you think you'll use it after you are going. Plus the kite lifts you out of the water anyway, gives you flotation.... just dont crash it

A PFD3 rated vest is a bit bulkier than a vest like the Naish Defender (not PFD rated but the Naish vest still gives you useful bouyancy). I have a Ripcurl "The Bomb" vest (PFD3 available from waterski/wakeboard shops). The more expensive PFD3 waterski vests still look OK on - I don't even notice mine 5 minutes after I put it on - plenty of buoyancy and keeps me warm on cold days. Awesome rib protection, but you need to wear a seat harness. Get a size smaller than you think when you try it on in the shop - vests stretch at least 10% when wet. If it's too big it rides up around your neck and armpits. You may not want to use the vest when you are up and going in a few months time - but the day may come when an equipment failure means a long swim. Or you are learning kite loops...

pfd's are also useful for other sports where you are required to wear a life jacket, i.e wakeboarding, sailing etc

GO A DAKINE IMPACT HARNESS COMBO... I absolutly love mine. I have no fear trying massive new movies and landing flat on my back with it on, such an awesome peice of protection.