I have one of each and raced a P-16 alot. the Hobie carries more sail area (bigger jib) and all in all it is probably faster. I prefer the P-16 myself, but they are both fun. As far as weight you should be able to carry more on the P-16, there is just alot more hull (flotation).Used Parts for the Hobie will be much more readily available.
Hope this helps,
Todd

"I said, now, I said ,pay attention boy!"

The cure for anything is salt water - sweat, tears, or the sea
Isak Dinesen
If a man is to be obsessed by something.... I suppose a boat is as good as anything... perhaps a bit better than most.
E. B. White