Our previous house had a wall double oven. We absolutely LOVED it. I do realize how costly they can be, but if I were redoing my kitchen and had the space, I would completely and totally get a double wall oven again. It was so nice to not have to lean over to get stuff in/out of an oven. Plus we have L. kids, and with the ovens being a L. higher up, I didn't worry about a child running around the corner and landing in an open oven (I realize that's probably me just being really paranoid, as I don't sit there with the oven door open for long!).
Our current house does not have a large kitchen, and it had the space for a single range. Since we loved the double oven so much at our previous house, we opted for a double oven range. It serves our purposes just fine. The top oven is smaller...that is true. We use it the most, though. The bottom oven is really a full size oven that starts at the ground (imagine taking out the bottom drawer that is usually on a range and replacing it with a smaller oven....only that smaller oven is on top). You'll still have a full size oven for your big holiday dinners, and you'll have the smaller oven on top to do bread/casseroles/etc.
SO, if I had a choice, I would do a double oven built into the wall. If I had to go with a range, I would choose a double oven range. :)