I have a GE 240v Advantium; it has a real 1500w heating element in the back that with a convection fan provides heat for baking. Although that's different than the upper and lower heating elements in a "real" oven, I haven't found it makes much different in routine cooking. The 240v Advantium wall ovens have a wire shelf rather than the round booster tray used on the 120v models. I find it works fine as a real oven, albeit a smaller one. Of course it's only available in 30" width (the 120v/15a model is available in 27"w as well). I haven't used a Miele speed oven so can't compare the two.

I have the 24" base cabinet in the basement for my old 24" Maytag oven, (decided to keep it as a back up). It fit perfectly: just slid into the box.

Here is my combi holding three pans of cookies. Pans are jelly roll size, which is the largest generic size that fits 24" oven. Half sheet pan is a little too big. However, using Miele's own baking tray which is about the same size as half sheet, but fits directly on the rack, will allow bigger batch of baking. Cooking three sheets is ok, but there will be a bit of uneveness around the side of yhe pan i.e. it will be a little bit more brown. Full size oven will have 5 racks. So it can hold more sheets. Or you can cook 3 sheets and probably get more even cooking than cramming in 3 sheets inside a combi. Another option is waiting for a new full size 24"x24" combi DGC 6860 and DGC 6865. They are already released in Europe. In Australia, we still have an older model DGC 6660. XXL size will have 4 racks and 68l cavity. New line will also have the plumb-in version too, 6865.

It has all the normal oven modes including broil plus the micro wave. The speed modes combines the two and you can adjust the power level of microwave it uses. I think the max is level 3. I don’t use the speed mode often but it worked well when I have. It’s a great small oven.