Convenience is king nowadays--especially in the produce section. Don't feel like peeling and cutting up carrot sticks? Buy a bag of them. Tired of scraping your knuckles to make coleslaw? Then help yourself to a load of shredded cabbage.

But it's those bagged leafy salads that are really tempting, especially if you hate cleaning and washing heads of lettuce. They all advertise that they've been thoroughly washed and have no preservatives, but just how fresh can a bag of cut-up lettuce be? And what does all this convenience cost?

We rounded up two dozen varieties, concentrating on mixed green salads, and tested them for taste, smell and looks. A couple did very well; a few were truly terrible. Most ended up in that vast middle ground of downright average. And all were much pricier than lettuce bought the old-fashioned way--by the head, that is. But we learned a lot along the way.

It pays to rifle through the produce bin and find the bags with the longest "use by" date. The same type of salad in the same display can have dates that vary by as much as a week.

Don't go by the date alone. Look inside the package. Do you see brown-edged pieces? Evidence of wilt? Chunks of iceberg that need more deconstruction or romaine leaves the size of your hand?

Take a close look at what types of lettuces are included in a particular mix. A better indicator than the hype on the bag (what is a "premium" lettuce, anyway?) is the ingredients list on the back, which will start with whatever is used predominately and end with what's used the least (that's where pricey radicchio often ends up).

Stay away from blends that include carrots; they tend to give the whole bag a decidedly unpleasant smell.

Be wary of salads containing endive and escarole. We found them to be almost uniformly tough and bitter.

The 24 salads we sampled came from four companies and can be found at most supermarkets. We tested bags with the longest "use by" date, settling for whatever the store had available on testing day. Several testers in our group, advocates of bagged lettuce, have changed their minds and are going back to buying lettuce by the head, washing it at home, spinning it and bagging it. Here's how these bagged lettuces stacked up, brand by brand.

DOLE SPECIAL BLENDS

It might be the largest producer and marketer of fresh fruit and vegetables in the world, but it's got a way to go with their salads in a bag. We had to pick through the Italian Blend (about $2.80 for 10 ounces) to find the best bits of romaine and radicchio, while the European Blend (about $2.80 for 10 ounces), opened one day before its "use by" date, was on its way to being compost. The American Blend (about $2.80 for 12 ounces) was remarkably good. Available at Giant and Super Fresh stores.

EARTH GREENS

This Salinas, Calif., product is certified organic, and it is a little pricier than some other brands. We found the Far East Asian Mix (about $3 for 5 ounces) to be the best of the salads we tried and especially liked the mix of whole baby leaves. But two other blends, Early Spring Mix and Italian Mix, were plagued with oversize leaves, old romaine and many brown edges. Available at Fresh Fields and some Giant stores.

FRESH EXPRESS

This was the first company to bring a national brand of bagged salads to the market--that was back in 1989--and the first to use what's called "modified atmosphere packaging"--the technique that allows the bagged lettuces to "breathe" to stay fresh.

Alas, too many of Fresh Express salads we sampled tasted anything but fresh, even though all had adequate "use by" dates. Fancy Field Greens (about $3 for 8 ounces) delivered the promised curly endive and frisee, but they tasted old and tart; Garden With Romaine (about $2 for 12 ounces) smelled downright awful. And stay very far away from the Veggie Lover's Salad Blend (about $3 for 12 ounces). On the plus side, the Riviera Blend (about $3 for 8 ounces) contained a lot of nice butter lettuce. Available at Giant, Safeway and Shoppers Food Warehouse.

READY PAC

This brand gets the consistency award. Five of the seven salads we tried from this California company were top-flight, with lettuce torn into just the right size and nary a brown edge in the bunch. Only the Sonoma (about $3 for 6 ounces) and, oddly enough, the Harvest Crisp Melange (about $2 for 12 ounces) from Ready Pac's Organic line, were inedible. Available at Fresh Fields, Safeway, Shoppers Food Warehouse and Super Fresh.