Anyway, two years ago I crossed Martino's Roma with Black Krim. Martino's Roma is a very productive paste tomato that seems resistant to blossom-end rot (at least in my garden). Black Krim is my #2 favorite tasting tomato (behind Pruden's Purple). Last year I grew out the F1 generation of plants. They all looked exactly the same, as expected (a somewhat flattened spherical red tomato with paste-tomato-esque flesh. This year I planted out 16 plants of the F2 generation. Although 16 plants probably isn't enough to see the entire compliment of genetic variation, I had to limit myself due to space.
My plants started flowering in very early June and I'm already starting to see some baby tomatoes. I was able to find fruit on about 6 out of the 16 plants so far, and it looks like there are two main fruit shapes:
A ribbed, flattened beefsteak shape, similar to Black Krim.
And a roma-shaped tomato, somewhat similar to Martino's Roma.
I can't wait to see what colors they turn as they ripen. I'm hoping for a paste tomato that has the coloration and flavor of Black Krim, but they paste-consistency and disease resistance of Martino's Roma. I'll just have to wait and see!