I use convection for most things. The only time I don't use it is for things that require bottom heat to rise like souffles and popovers.

I use convection often enough, and both ovens often enough that I didn't want to limit myself to convection only in the upper oven.

You have to consider how often you'll use both ovens, and if you could see yourself having problems. For me, double convection was a must but for lots of people it might not matter.

I use it when I am using a pan with low sides.

I don't think I ever use the 'regular' programs, other than broiling.

I had a convection only oven in the UK, for over 10 years, which is pretty usual in Europe.

When we redid the kitchen here, I kept the old non-convection oven, wired up in the basement, in case I needed a second oven. To be honest, in two years I've never used it or missed it despite daily cooking!

I'm still learning my oven, but I've found that if I'm making a new to me recipe that was written for a non-convection oven, that it's better to do it with the convection off. It doesn't seem to matter for casseroles and covered pots, so I use it just because. I have a convection broil setting which is great for lamb chops cooked on my cast iron grill, but not so much for anything thicker. It's good for standing chicken roasts if they aren't in a pot.

What I didn't guess before I actually got to use it was how much I'd love convection for cookies and appetizers. Being able to bake them all at once and get them over with is really fun! I only have one large oven (and two specialty ovens), so multi-level baking of puffs (choux paste) makes a big batch into no big deal instead of waiting for the oven to cook for each tray.

Convection is considered a problem for anything that doesn't like the turbulence. That would be anything egg risen, like a souffle or sponge cake. Some people include custards as well, which might include quiche. I haven't tried custard with convection, so don't know for sure. I've have found that small, lean beef roasts can get dried out with the convection on, as well.

General rule: Use convection with anything that won't get dried out or blown around.

If a couple hundred dollars will make a big difference to your budget, I'm sure you can balance your cooking so that you only need the convection in one oven. Multilevel or multipot cooking is where convection makes the biggest difference, so dozens and dozens of cookies for the bake sale or reception would be a lot easier with two convection ovens. For Thanksgiving, you can put the turkey and maybe something that isn't very touchy in the non-convection oven, and the other things in the convection. BUT, if you were planning to buy a pair of stylish new boots or a night out on the town, it's worth forgoing that to not have to worry about which oven you put what in when, and just get convection in both.

I use convection for meats/poultry, roasting veggies, frozen foods, open casseroles, multi-rack baking of cookies and granola, and things I want particularly crispy and brown.

I don't usually use it for baked goods, such as pies, cakes, breads, muffins, and pizza. Things brown too fast/too much by the time the insides are done for my taste.

I have an dbl oven with one convection and one not. The only reason I wish they were equally featured, because I love to use the probe, and miss it in the bottom oven.

We have a Dacor double oven and both have convection. I know I don't use it as often as I should. I was looking forward to convection bake but it just didn't seem to work well for cheesecake or pumpkin pie so I bake them on regular bake. I'm the first to admit that my disappointment might just be user error and maybe I should try again.

Cookies are great on convection, especially multiple trays.