Okay! So, I got ripe fruit, today. It's like a large, yellow cherry (a bit more oblong than some cherries). The F1 was red; so, it looks like the color should be stable at yellow, and the leaves stable at potato leaf.
The taste is sweet. It reminds me of Medovaya Kaplya with a bit more complexity, and a more tomatoey flavor (a tomatory flavor is a bit unusual for a yellow tomato, in my experience, but it's not super strong, and it doesn't interfere with the Medovaya Kaplya type taste). It's really good. It reminds me of Esterina F1's flavor, but it's not quite the same. The fruit is firm-ish, but not crunchy (it's soft to the bite). It didn't split when I removed the calyx. Medovaya Kaplya is probably at least a tad sweeter, but they're both sweet.
Here are two pictures of the same fruit (there's at least one more ripe one to harvest):


Due to the shape, I'm guessing a round tomato is the patriarchal parent of the cross. Round, red, regular leaf, and perhaps not smaller than that. McGee? Monroe? Mountain Princess (well, it's not always round)? My RL Kimberley offtype? I'm not sure what else I grew that could qualify. Creole? (That's a little big for its size.) It was probably McGee; I'm not sure of what other tomatoes would qualify. That should make it extra nice for Texas, if so (I got my Medovaya Kaplya seeds from someone from Texas, and McGee has a history of being grown in Texas).
Location: SW Idaho, USA
Climate:
BSk
USDA hardiness zone: 6
Elevation: 2,260 feet
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