I've got one. I have it for almost years. I've got a twin supercharged 454 and it runs around 90 with a lab finished 26p, and has plenty of power for a 30p but the wife draws the line somewhere. Mine is the boat on the front page of their website and brochure. (My Dixie Wrecked)
My only complaint would be that it flex's a little too much and that in rough water the front of the boat is really close to the water, especially with people in the front. I've actually taken on quite a bit of water once and I didn't like it all with the kids on the boat.
The flexing is pretty muched fixed with the new ones though.
As far as the guy with one that will only do 50....He's got some other issues that arent hull related...Maybe intake/pump angle or something.
I defenitley would not get a jet, unless you only use it south of Parker. The gas mileage alone would scare me away from that.
Hope I was helpful.
The guy with the one that will only go a touch over 50 had the entire boat built by Placecraft, so if there is an issue with the pump setup there is only Placecraft to blame. The boat seems nice and being a tunnel it definitely rode better than my 21 would have in the same water. But if you're saying that he should be seeing higher speeds with the Marine Power 502, I'm sure he'd love to hear about it. If you know of other owners with jets and the 502 that are seeing better speeds, PM me so I can give you his information.
Thanks,
Chris