We went with the 4.3 - no microwave. We have been very happy with our decision. There are only the two of us but we have some "special needs" (food sensitivities that require a little more space than usual.) We had more than enough room, including freezer space, for all the stuff we needed for a 10 day trip in July.
We are not heavy into beverages, but always had extra room for a couple of IPAs, a bottle of wine or some spritzers - our rule being: if you take one out, you replace it with another to cool for the next time.
We NEVER missed the microwave, but brought a toaster oven that we plugged in outside in the screen room when hooked up. That was really nice. The space where the microwave would be put is left empty - with a door it becomes a pantry. The smaller fridge also allows another smaller compartment above the pantry, which has been very useful for keeping documents, manuals, shopping bags or more stuff
We also have a 12 volt cooler (Canadian Tire special) plugged into the cab of our truck when on the road; for juice, snacks etc. We thought we could use that as extra space if we didn't have enough room in the 4.3 but have never needed it.
Hope that helps - I guess it all depends on how many are in your group and what your own needs are.
Good luck with your decisions!