no personal experience, but i met up with a couple cruising the
bahamas in a bristol 27 with o/b well. this was back in the early 80's (or maybe late 70's) and they seemed perfectly happy with it.
nice thing about an outboard is it's usually a whole lot easier to
work on then an inboard crowded into the small space you're likely to find on a bristol 27; and when it finally dies, probably a lot cheaper to replace....