Best is actually Broan (or Best by Broan). It's more or less supposed to be a higher end Broan line. I don't think it makes a big enough difference; my recommendation would be to go with Zephyr again, especially when it comes to inserts.

I don't have a recommendation per those two brands, but if your range top is 36" you need to get a 42" or larger vent hood. The grease/oils/smoke/etc...moves up and out like a cone. We have been doing countless research the last two months on ventillation of gas range tops (we are going with a 48") and 6" wider than the range top is a minimum recommendation. Though for some reason all of the appliance places try to throw you into same size. Also, for hood blowers, take the BTU \ 100 = CFM of blower as a general rule.

Then you can take a stroll down the road of building science and backdrafting, make up air, etc...that comes along with powerful hood fans! YAY! not...