OK i disagree 100% with the hydro's needing 1/2 the power of a cat for good preformance. I have had a hydro with a reccomended HP engine and it preforms no way NEAR as good as what one does with a max horse power. (been there and done that and never again) They are very similar to the cat in many ways but have a centre hull which is obvious. However u still need to get the hulls up and working for a good ride, the more air under me the better i go. if u wanna do 12 or 15knots in a hydro and just cruise i hope u have good clears as u will get alot of water over the nose when u are travelling slow in a rough sea. I now have a 6.8 which was a 5.6 with a 225 and it goes great, i wouldnt and dont reccomend anyone to go just the rec horsepower on one of these boats, go max it will be alot better. these are just my thoughts - 6years experence owning and fishing out of one, extending and re designing one, boat builder bye trade and been in boating and fishing industry for last 10 years
The Multihull designs are great, they have there pros and cons, i dont know much about cats however i just finished fishing out of a 2400 Kevla cat with twin 140hp Zukes and the ride was aweome even in some crap weather, we come home when a front blowing i guess maybe 20knts with some good size swells here and there, doing i think lowest speed was 40ish km's and for the last 20km home we had it at around the 55 to 65km mark and it was a great ride, ive always wanted to see how the Kevla cat compares to the 6.6 in ride and it did not dissapoint one bit. The deeper tunnels in the KC makes it ride fantastic and stability is similar to the hydro but both boats are fantastic and since ive had a multi hull i would not go back to a mono in the same size.
Regards,
Mat