I've always grown my tomato plants in growbags laid on soil in my greenhouse. I sometimes grow F1 types as well as standard non-determinate types such as Ailsa Craig. Each year, the odd tomato or two falls on the soil in the greenhouse. This year, I've got a plant growing in the border soil which has obviously originated from a seed that's come from one of these tomatoes that have fallen on the ground. Although the plant looks quite deformed, it currently bears many bunches of cherry tomatoes.
I've tasted these tomatoes and they taste fine to me. However, as I understand it seeds from F1 tomatoes will not grow into F1 plants the following year. Because of this, if the plant has come from one of last year's F1 tomatoes, how edible should the fruit be? Should they taste the same as any other tomato? The plant may have come from a standard seed as far as I know.
A seed grown from an F1 plant is technically inbred, it doesn'y have two distinct 'parents'.
If it's fruiting, then the fruit will be just as edible as any other, but the fruit and the plant may be more susceptible to any of the common tomato 'illneses'.
what you have is an F2 hybrid, the offspring of an F1. While still edible and potentially ok it will not have carried all of the benefits of its parent plant so may differ in habit and taste and as Naz says, may be more susceptible to tomato diseases that perhaps the parent plant had some resistance to.