I just started a kitchen remodel and decided to give up my range and go with a cooktop and double oven. The double oven is the GE with Trivection. We are still going to need a microwave so I'm thinking about putting a electric outlet in my new pantry and put the micro there. I didn't want to take up counter space so we shall see how this works. My old micro was OTR and it worked good.
You might want to check out the GE Advantium oven. It also works as a microwave. If my kitchen had been smaller, I would have gone with that one for sure.

I would suggest going with a vented range hood. It has nothing to do with gas vs electric and everything to do with venting excess moisture from the house. The added benefit is removal of the heat and cooking odor, such as smoke and grease. Although I just installed an OTR microwave, I wouldn't recommend it for someone who cooks a lot on the stove. Their venting ability is not as good as a real range hood. Since my house never had a hood (Jenn-Air), now having at least a vented micro-hood is a dream. (Jenn-Air downdraft fans just can't get around the laws of physics.)

I would find the kitchen more appealing with a single oven and a microwave built in above it. I would be a bit leary, though, if they were identically matched. There are too many brands out there that excel at one product (an oven, for example) and then are just average at another (such as the microwave). Look for the models that really have the reliability, functions and features you need (deserve) rather than just looking like clones of each other. To me, a mismatched appliance set says that someone took time to research the right products rather than just walking into a showroom and saying, "Give me everything from Brand X in this color."

I recommend the GE Profile single oven stacked with a GE Profile Advantium (120) oven. Both available in 27 or 30".

That way you have the flexibility of an oven and either a microwave, a second oven, a speedcooker, a warming oven, or proofer. The Advantium does so many things, you'll love it! Offers complete flexiblity all in one unit.

We have had a GE Advantium OTR 240 Volt version in place for 9 years. We love it!

The Advantium 240 Volt version requires a dedicated 30 Amp 240 Volt circuit so be prepared for adding such a circuit to your home. But the difference between the 120 Volt Advantium and the 240 Volt Advantium is significant! The 240 volt version produces 4 times the cooking heat. Of course, installation costs will be higher and the oven itself is much more expensive (you can shop on Craigslist and eBay for really good Advantium prices. The SAC2000 and SCA2001 models are easy to find in all surface finishes.)

You can vent the Advantium to the outside (we do) or recirculate the air through an optional charcoal filter back into the kitchen. (Anyone know of someone doing this?)

We have used the Advantium for about 50% of our cooking during the last 9 years. There is NO preheat time! We've made muffins, chicken, fish, popcorn, baked potatoes (outstanding...only 5 minutes!...and those potatoes do not taste like microwaved potatoes), etc.

We have come to the conclusion to go the single oven with the convection microwave option for a few reasons.

A few questions about the GE recommendations:

1) Isnt the Advantium the one with the light bulb that cannot be replaced by the owner and requires a service call? (I may be confused with another model).

2) The current location of our microwave and oven is not vented and I would have to belief to get that done from where they will be located will be VERY expensive (it is a 2 story house with the oven location on an inside wall)....does it have to be vented?

3) How is the quality of the Advantium and therefore GE?

We are considering the Sharp R-930 Convection Micro and KitchenAid Single Oven at this point. Any thoughts would be appreciated. Thanks!

Ok so we are still thinking the KA Single Convection Oven with:

A) Sharp 930
B) KA Standard Micro (matches the oven)
C) KA Convection Microwave

I am just not sure how much use we will get with the convection microwave. Again, any thoughts are appreciated....I have called/spoken to several appliance sales people both big box stores and online stores and the spectrum of answers I get is amazing!

If you are set on KA, I believe KA has an speed cook/convection oven similar to GE's Advantium. The reason I chose the GE Profile line over KA was:
1.) the interior of the Advantium held a 9x12 pan, KA's did not (helpful for casseroles and brownies)
2.) I just felt the quality of the GE Profile seemed better than KA when I looked at them side by side.

The Advantium comes as a wall unit that looks just like second wall oven, and thus does not require venting. So I would recommend that versus the OTR Advantium for your situation, which eliminates the venting question.

As far as quality, I haven't heard anything about the light bulb thing. But, my last Advantium was an OTR and it was 4-5 years old and going strong when we remodeled. A friend of mine now has it over her range and it's still going strong at 6-7 years old. My new Advantium, 18 mos old, has had no problems at all.

As far as how much use.... I use my advantium for baking and speed cooking way more than my oven. In fact, I rarely use my oven unless doing a large batch of cookies, or multiple pizzas, or a big turkey. Pretty much everything else gets broiled (fish), roasted (veggies), baked (brownies, biscuits, frozen breads,) or speed cooked (frozen meals, pizzas, chicken nuggets, etc) in the Advantium. The thing I love most is being able to pull out a frozen pizza (or anything else frozen) and throw it immediately into the Advantium. No preheating required and the pizza is done in less than or about the same baking time as recommended. Thus, the time saved is the preheating time, and you haven't wasted energy heating up a larger oven. So not sure how much you'll use it???? My guess is ALOT - I know I do!

As I said, pretty much all I've said will also apply to KA's version of the Advantium --- but, the KA won't hold a 9x13" which was key for me... at the holidays, I was able to stack two 9x13 casserole dishes (sweet potatoes and green bean casserole) and bake them at the same time while the turkey was down below in the single oven.

Hope this helps!