Cooktops & wall ovens: features and flexibility.(HOME: Dream kitchens for less)(Buyers guide)

Separating the cooktop from the oven keeps two cooks from spoiling each other's broth while putting both these appliances closer to eye level. But you'll have to find the space and money--and check the reliability--of two appliances instead of one.

Our tests have found that pricey cooking appliances don't necessarily outperform their mainstream counterparts. And our new repair histories for wall ovens and cooktops show that spending more doesn't guarantee better reliability, either. Some of the most costly brands, such as Dacor, Jenn-Air, Thermador, and Viking, were relatively repair-prone.

What higher prices often do buy is better design and more features. Induction cooking, for example, is available only on cooktops. Convection is common among wall ovens, not so on ranges.

Induction cooktops offer faster heating, flawless simmering, and burners that shut off automatically when you remove the pot. Electricity passes through the magnetic elements under the cooktop's glass surface, so they heat just the pot and remain relatively cool. But they typically cost two or three times as much as mainstream gas or electric cooktops and the technology's reliability is unproven, which is why they're not in our Select Ratings. A Kenmore model costing $1,800 performed as well as the pricier Gaggenau and Viking units we tested, but its controls were finicky, sometimes reacting to our touch, other times not. And you may need special cookware for induction (if a magnet sticks to the pot, it's OK).

Ovens with convection use a fan to circulate hot air, so you can bake and roast at lower temperatures and for shorter times. Most wall ovens with convection automatically convert these differences for you. But the …