Because of paste tomatoes’ dual nature, both of these conflicting judgments are sound. What gives fresh-eating tomatoes their thesaurus-exhausting exquisiteness of flavor is the jelly around the seeds and the high water content. Slice into a Green Zebra or Mortgage Lifter and it’s advisable to have a tea towel nearby to sop up the mess. But paste tomatoes have few seeds, little jelly, and walls that are thick and dry, with a texture reminiscent of the cold, tough tomato rinds that are so traumatizing in side salads. They are generally not very sweet.
Cook a paste tomato, as its creators intended us to, and its flaws become virtues. A non-paste tomato is so juicy (i.e., watery) that cooking evaporates almost its entire substance, along with its flavor. The opposite happens when you reduce paste tomatoes: Rather than boiling their qualities away to nothingness, you approach their essence. A well-reduced sauce made from paste tomatoes is so silky that I've adopted the fussy, inconvenient steps of blanching and peeling the tomatoes beforehand, so that not even a fleck of tomato skin spoils the sauce’s texture.
You'll be wanting the names of some worthy paste tomatoes. By all means: Jersey Devil, Polish Linguisa, Opalka, Hungarian Italian, Goldman's Italian American, Principe Borghese, Long Tom, the miniature Juliet, and the mighty Amish Paste. If you have a garden, plant some next spring, especially if you're short on space. A lot of paste tomato plants are short, bushy “determinates” that give most of their tomatoes within a few weeks and then go into decline. They are docile as doves. Whereas indeterminate tomato plants bear fruit continually throughout the summer and swell so monstrously that they can pull even a securely staked tomato cage clear out of the ground and flop over, killing themselves and neighboring plants simultaneously.
The mild heresy of cooking garden tomatoes has lured me into another, more troubling transgression: replacing heirlooms with commercial hybrids, at least for cooking. For fresh-eating tomatoes, there's no doubt that you should be growing heirloom varieties, because, sorry y'all, they do taste better than modern hybrids, ceteris paribus. (The same mutation that gives hybrids their pristine red skins also suppresses the production of the compounds that give a ripe tomato its most elusive and complex flavors.) But with paste tomatoes, it doesn’t matter as much. The process of cooking can wash out some of the coarser differences between hybrids and heirlooms, and indeed between ripe and unripe.
If you're skeptical, I recommend the following experiment: Make two sauces simultaneously, one from heirloom paste tomatoes, another from ripe, store-bought Romas. When I did this a few weeks ago, I noticed a difference—the sauce made from the heirlooms was richer, sweeter, and thicker—but it was a difference of maybe a few percentage points, like what you get when you compare chimpanzee and human DNA. (Some may see this as a profound difference, but chimpanzees are pretty amazing animals.) If you grow or can afford to buy heirloom paste tomatoes, go for it. If not, Romas are cheaper, easier to find, and almost as good. But don’t buy canned unless you’re stocking a bomb shelter.