circumstances when I would prefer boots (maybe in snow). I love the Saucony Peregrine. This was a strong recommendation from the folks that run the site Cleverhiker. I tried the Altra(s) but do not like the boxey fit - doesn't work for me.

A couple things... The idea that you need heavy hiking boots for ankle protection, I believe to be a myth. The extra weight on your feet is far more taxing than if you had the same addition of weight in your pack. If you are in shape, your ankles should be strong enough without artificial support. (The only thing I buy is that a rock plate under foot may be helpful when carrying a heavy pack...which most trail runners will have...). Also the need for fully water proof shoes. There are several arguments for having shoes that can breath and can dry out. For one, once your feet sweat you are virtually guaranteeing that they remain wet in water proof shoes.

Check out this article for reasons to ditch hiking boots...