Steve,Mountain Fresh F1 and all the other ones listed in the link below were bred by Dr.Randy Gardner,formerly with NCSU a tFletcher in NC.

Note that all of them are determinates and are primarily grown by commercial farmers for market sales.

Two are missing from the list below, one is Mountaint MagicF1 and the other is Smarty F1, and those two I've grown and like very much. Smarty is a grape varietyoffered by Johnny's and MM F1 is available at many placesif you do a google search.

So all of his are very popular but primarily with large scale farmers, anda few with home gardens as well.

Carolyn

Here is a link that might be useful: Dr. RandyGardner's hybrids

So, my question to you folks is this: If these tomatoes are so good, why aren't they more popular?

In part because they are, relatively speaking, new varieties. But mostly IMO because there are so many varieties that are so much better for growing in the home garden. I grew some of them 2 years in a row shortly after the seeds became readily available. And while they were a good tomato, they can't compare in flavor to many of my other favorites.

As Carolyn said, they are primarily a commercially grown and marketed hybrid variety developed for that purpose and that aspect doesn't appeal to many of us when there are so many others to choose from.

Dave

Carolyn & Dave,
Thanks for your quick responses.
Steve

They are doing well for a farm down the road - he said he had heirlooms but there weren't many at his stand and I didn't see them on his table at market last week. Johnny's says it's able to tolerate cool and wet conditions, must also be able to tolerate heat if it's done well here this summer. He told me he lost a lot of (heirloom?) tomato plants in June, I'm losing them now, and not a lot of fruit set with the wild temperature swings.

Here is a link that might be useful: Mountain Fresh at Johnny's