I opted for a separate oven and cooktop because I wanted an electric oven and a gas cooktop. Electric is supposed to be better for baking and consistency in temperature, my old gas oven seemed to cook unevenly. I have been happy with my electric oven (which has a convection option). I like gas for the cooktop because it gets to temperature quickly and can be adjusted more finely. My cooktop has two extra low burners which cycle off and on which I like. I didn't have room for two ovens so the wall that holds my oven has a microwave wall unit, the oven and a warming drawer (love the warming drawer!). If you are o.k. with all gas or all electric then one unit could work. If you often find yourself needing to put two things in the oven at different temperatures at the same time, two ovens are important. I have never had a need for more than 4 burners on the cooktop. The warming drawer helps a lot because I never need to keep things in the oven or on the cooktop after they are done just to keep them warm.

Robbi,
Thanks for the quick response. I agree with you about electronic ovens and the 48" ranges I am considering have gas cooktop and electric ovens ( duel fuel). Do you gave a regular microwave or one of the multipurpose ones? Also can you bake in warming drawer? Thanks!!

I have a 36" gas range with oven and a double wall oven electric, I do not agree that gas does not bake as well as electric but do like gas for bread and pizza much more than electric. My range has 6 burners and I cook and entertain a lot and this combo works really well