According to my web site statistics, I see that someone was interested in "negative aspects to the GE Advantium" oven. Since we own an Advantium oven, I thought I'd take a moment to discuss the good and bad about the oven since we've been using it for about 4 months now. We have the wall oven model which looks much like a typical wall oven, although not quite as tall.

Great/Good

• We can cook things that would have required the oven much more quickly. It's awesome for last minute decisions. I can decide to make a toasted garlic bread with cheese side for a meal and in 4 minutes, it comes out toasty and tasty, without the feeling that it was microwaved (which, if you choose to use the manual mode, you can selectively control).
• Pizzas -- fast! We had a frozen pizza last night -- from start to finish cooked in 9:15 seconds.
• Fast cookies.
• Gadget-y. All ovens should be this versatile!
• Crisp foods, oven quality. Microwave-style egg rolls come out crispy, not soggy (although see the bad list for a sticky problem).

Bad

• Things stick to the metal pans sometimes quite fiercely. I'm never sure what will stick, or how to prevent it always. Usually not terrible, but it can be quite destructive to an egg-roll for instance when part of the the egg roll remains stuck to the pan after removal.
• Loud. The wall mounted unit is quite loud when running. There are some very noisy fans built in to keep the unit cool. The positive side is that they don't run very long after the unit has stopped heating (depends primarily on how long the oven was used and what settings were active). It's loud enough that you wouldn't want to eat with it running. We have a second oven -- a convection oven -- which isn't nearly as noisy as the Advantium.
• Manual microwave mode only has settings in 15 second intervals and the menu system isn't as obvious as a typical microwave
• Only a 12 inch circular cooking surface.
• Intimidating. My wife still hasn't used it much, in part because we have a second microwave tucked away underneath the countertop. I admit that I typically will use the microwave first if I want to defrost or just do "microwave only" things.
• Minor: Being a geek, I wish there was a way to upgrade the menus to include new recipes (not aware of any way to do this besides the option of programming in custom recipes). Maybe in a future version and future kitchen ...

Unknowns

• We really haven't experimented with the variety of menus much yet. Hopefully now that the house is starting to feel settled, I'll read through the included cookbook to look for some of the more interesting recipes.

Update! I've created a new review here, several years after this post with a few recipes, and further feelings on the advantium.