I wish I knew what the "heirloom tomato" really was as it has produced
fruit that is everything that exemplifies a home grown tomato with
indescribably delicious complexity of taste.

I don't believe heirloom tomatoes are supposed to satisfy that
criteria, you can saved the seeds for next year, that is about it.

There seems to be some misconception that modern hybrids were bred
solely for looks and shelf life, this is of course true for some
hybrids, used by commercial growers. But the other side of the coin is
that another group of hybrids have been bred solely for taste for the
home gardener, that are far superior in taste to any heirlooms. The
hybrids took over pretty quickly when introduced was no accident, they
are better in every way, but you have to pay for the seeds every year.