The models that are basically countertop ones an cost $500-$900 are basically good for baking chicken nuggets, frozen pizzas, and other heat and eat processed foods.

They are not a good substitute for a real oven if you want to bake cookies from scratch or cook a turkey or quiche.

They are also fairly deep so placing one in an upper cabinet space is not really practical. They generally need to be placed in a tall full depth cabinet like an oven tower.

Having seen your other posts - I think you need to enlist the services of a professional kitchen designer to gauge and refine your needs within the constraints of the developer , then come up with feasible plan to take to the builder.

We had space limitations and put in a Sharp 930 in cab/shelf builtin. Has run 9 years, no problems--turned out to be a good surprise. Our usage experience is opposite of above poster--we use it for cookies, small roasting chores (chicken breasts, tenderloin, etc) and for baking ( even popovers come out just fine). It's also a lot easier to fire up than our Wolf AG range oven and doesn't heat up the kitchen anywhere as much. It's light years above a toaster oven. The larger internal size seems to make the micro function a little slower (I've noticed CR said same thing) but it's just a matter of adjusting cooking times slightly longer, not a quality issue. The dual mode requires a little practice (or for some cases like me to actually read the manual . . .) but is effective (like for baked potatoes in 20 minutes that aren't micro mush). We don't use the broil function as it really isn't a broil at all, just high heat. Because we roast in it and it's SS inside it's got to be cleaned and that's a bit of a chore (SS scrubbie and BKF) a few times a year. If it broke we would replace it with the same/similar product.

I have had two Sharp Convection Microwaves (not speed ovens, just works as either mw or convect) over the past 20 years. Very reliable and work great as a small second oven---not for true baking, but for other oven dishes, works great. I have only one wall oven and so this bridges the gap so that we did not need a double oven. I'm doing a kitchen remodel and considering the newer speed ovens that both convect/mw at the same time. Anyone have advice as to how you like your speed oven?

My above post refers to convect/mw--that's the "dual mode." There other speed ovens that use light, others can weigh in on those.

The GE Advantium Oven 220 olts is wonderful! We hardly ever use our oven anymore. We bake cookies that are really good and we even make a browned grilled cheese in it! You can pretty much do anything in it. It is a speecook oven, convection, microwave and a warming oen! It was a great purchase, especially for someone with limited space!