Re: trihulls? good or no good?
I have a 15' Invader, 1976, with a Merc 65hp O/B. I re-did a soft spot in the floor a few summers ago - took me 2 months to do about 20 hours worth of work. That's cuz I had NO CLUE what I was doing. But it all became obvious as I tore things apart. Just do it.
One thing I've noticed - my boat's gunwale is only about 16" above the water. My Dad's old 18' triHull had a good two feet. That could make a difference in rough water, I think.
Two years ago I was out on a lake at 7pm and it got windy. I had 2 women and 2 boys with me in the boat. I stood up to drive, and kept the speed down, and we made it back home no problem. Only later did I find out that my passengers actually thought we were going to sink out there! But I never had any concern.
This year, after fireworks on July 4th, I was putt-putting back to shore and heard screams. A wave (actually, another boat's wake) had broken across the bow and drenched my two passengers in front! I'd never had that happen before! Unfortunately, my cousin's new $400 digital camera, which was in a jacket pocket, ended up on the floor in 2 " of water.
Now it's time for a bigger boat. I rented an 18' open bow v-hull, and my 8 year old son complained that it was "too cramped". The tri-hull gives a ton of space, and it FEELS bigger. I'd sure like to find an 18'tri hull that was less than 20 years old, but they don't exist. I asked in this forum a year ago and was told to look at "Deck Boats". But they cost a minimum of $10 grand in decent shape (used) and I don't have that kind of money.
Best of luck with yours new boat. I think you'll be happy. Just take it slow in the rough stuff.
Dave