I'm a new 170 owner
We bought ours this summer. Like you, I had some concerns about stability and actually contacted about 25 Hunter 170 owners for their insights before buying. I also considered the Catalina.The boat can be sensitive to weight placement, no doubt about it. Still, it has been more stable than I expected. We had it out in a variety of conditions up to about 15 mph winds. We ordered the Hobie float, and that gave us some peace of mind, although I only had one instance where I thought we might actually go over....didn't do it though. The new 170's have a heavier centerboard and come with reef points installed in the mainsail. When in doubt, we reef the main or sail only under the main.The boat is easy to rig and take down and is fairly fast...we've actually cruised right past other boats on a parallel course even when our mainsail was reefed. I think in the long run the fact that we have to cognoscente of weight placement will make us better sailors, although it can be a little frustrating at times.We've had as few as two adults and as many as 4 adults plus one child on board, although we seem to do best with three adults. For some reason, the weight works out the best for us that way. Also, it handles best for us between 7-10 mph winds.