Hey, Eyes.
Free seeds are great! The main question is what genetics you have. The answer is maybe.
Sure, the seeds are likely 50% of the strain previously in the jar, but
consider. . .
- What are the genetics of the pollen donor?
Same hermie plant? Probably the same strain. Or, maybe your friend purposefully made the seeds - good to grow.
Another strain in the grow? This results in a new hybrid.
Wild, air blown pollen from an unknown source? Worst of all possibilities - 50% male seeds, unknown THC content, unknown yield. So, why bother?
Ask your friend about the seeds.
A bit more info is good. Or, why worry? Grow some out and see what you get.

)