I used a 13'-ish Zodiac with a 30 HP outboard while working on a tall ship in South Jersey. Ripped thru the river, even with strong current, and was great in the Delaware Bay, even in the middle. You can screw eyehooks into the decking and attach any bags or items you have with caribiners (sp?) to protect them from bouncing out. The only time I was fearing capsization and decapitation via motor was when I was tending in the Delware River and a tug blew by and left a HUGE wake. Didn't have time to angle in. I kissed the dock when I got back. But yeh, they're real stable, and you can fit 6 people easy in an empty boat. Never found a good way to apply the registration numbers, as they would scrape off while tending and docking. They are way easy to launch, especially if you get a hard bottom (I'm not sure if they come soft, but I feel like I've heard of those before). 30HP should suffice for a motor. With it, I've even towed much larger boats filled with silly tourists that ran out of gas with no problem. $60 for us, and none for Sea Tow.
I would highly recommend that you get your mitts on one.