Microwave ovens seem to get more complex each year. Sales-hungry manufacturers are heating up their product lines with greater capacity, convection cooking, and other features – such as grilling and browning – aimed at homeowners who want a second oven without having to remodel.

But when it comes to performance, not every model shines like its stainless steel finish. Still, choosing a microwave needn’t be difficult. Here are some basics to consider.

Pick type and size

Microwave ovens can either sit on a countertop or hang over a range. Countertop models take up space, but the larger units tend to have more capacity than most over-the-range (OTR) models. OTRs save counter space, but require installation. What’s more, most of them do only a fair job of venting smoke and steam compared with range hoods, which are very good to excellent at venting.

As you’re considering the size of a microwave you’ll need, take time to think inside the box. Manufacturers express their ovens’ size in cubic feet – a number usually displayed on the unit or its package. But larger overall size doesn’t always translate into more usable capacity – our measure of what can actually fit onto the oven’s turntable or sliding tray. Some larger models, for example, might take up more counter space than midsized ones but have the same or less usable capacity. We found models with identical exterior specs that varied by as much as 0.9 cubic feet in usable capacity.

Choose features by need

Added features such as convection cooking, and grilling and browning functions can often add $200 to $300 to an oven’s cost. However, in our tests none of them consistently provided the results you’d get in a regular oven.

Other features – such as presets or shortcut buttons, and automatic settings for popular microwavable foods like popcorn or potatoes – can simplify use. Child lockouts, too, can be helpful, because they keep little hands out of trouble. That’s especially important on convection models, where the unit and dishes can get very hot.

Recommended models

Regardless of size or features, most ovens we tested did a respectable job of basic microwaving tasks such as defrosting meats, reheating leftovers, or making popcorn. Following are some notable models:

¢ Countertop. For a basic unit, we liked the Kenmore (Sears) 6325(2) (0.9 cubic feet of usable space) and the GE JE1460(B)F (1.0 cubic feet of usable space). The Kenmore ($110) was easy to use and excelled at defrosting. At $130, the GE was slightly more spacious and was better at heating foods evenly – though it scored a notch lower at defrosting. Both are CR Best Buys. For a countertop model with more features or capacity, consider the Daewoo WM1010CC ($150; 0.7 cubic feet), the GE Profile JES2251SJ(SS) ($220; 1.5 cubic feet), or the GE Profile JE2160(B)F ($170; 1.5 cubic feet). The Daewoo was the only oven that featured convection cooking and did very well or better with basic tasks. However, it lacks sensor-controlled cooking functions. The GEs are microwaves only, but offer large capacity and more features than most.

¢ Over the range. Our top-rated OTR model, the LG LMV2053(SB) ($300; 0.9 cubic feet) is also a CR Best Buy. It scored better at heating foods evenly and defrosting than models twice its price. If you’re looking to conserve more space, the very good Kenmore Elite 8083(9) ($530; 1.6 cubic feet) was the most spacious OTR unit we tested. That’s partly because it has a sliding tray instead of a turntable.

Highest scoring among OTR ovens with convection cooking were the Whirlpool Gold Velos GH7208XR(Q) ($870; 1.1 cubic feet) and the GE Profile Spacemaker JVM1790(B)K ($650; 0.8 cubic feet). Although very good overall, we weren’t impressed enough with these – or any other convection-equipped OTR model – to recommend them.

Visit the Consumer Reports Web site at www.consumerreports.org.