Having owned both I can say they both have positives and negatives. I think it really depends on personal preferences. Both boats are great for sailing the inercoastal here in Florida.
I liked the fact that there are fewer mechanical connections on the Prindle frame which make it a stiffer boat. Especially if it has some years on it. I prefer the rudder system of the H16. With the deck level trampoline of the P16 you feel like there is more room to move around. The H16 raised trampoline keeps you a little higher off the water and dry. Especially if it has a solid vinyl tramp. The H16 is prone to pitchpoling in rougher conditions while the P16 isn't.
I've said this before on this forum and I think some people say so what but I think it's kind of significant. When I got back into sailing cats I wanted a used boat that I could keep going for many years. I found a P18 and it needed some help. I had difficulty finding some parts so I checked into an H16. I was amazed at how many resources there were for these classic boats. Since P16's are no longer made I went with Hobie.
I like them both but would stick with Hobie.
Good luck in your choice and I hope you find what your looking for.
i bought a p-18 last fall. with a little searching i have found any parts i've needed, only problem i've had is my money situation. the prindle parts seem to be very price comparable to the hobie parts. if ya want a boat for taking a couple few freinds out after a couple adult beverages, i suggest the p-18. my buddies h-16's are without question faster, but by the afternoon we were always on my boat.
if i could get the chrysler cat cheap, i'd buy it. ive owned 12 or 15 sailboats over the years, most of them were junk in most peoples eyes, but ive had a f--kin blast with everyone of them. boats, of any type dont have to be pretty to be fun. making parts you cant find isnt that hard,and ya just might be able to give some kid living around you a deal this summer and a reason to get into sailing. remember guys sailing no matter a cat or a slug, is for FUN and enjoyment.