Cool, tho of course theyre not related to true potatoes (solanums)
How do they taste?

They're delicious! We ate some last year. I couldn't tell any difference between these and the ones you buy at the store. There's so many things I want to do with this plant next year, so I replanted these instead of cooking them.

Found on net:

Botanically known as Ipomoea batatas, the sweet potato is a member of the morning glory family, Convolvulaceae and is closely related to the morning glory vine (I. purpurea) and the leafy vegetable, kangkong (I. aquatica). It is not related to the true potato, which is a member of the tomato family, Solanaceae.

There are ornamental sweet potato varieties grown exclusively for their decorative foliage. These ornamental varieties may also produce edible underground tubers but they are usually less prolific and tubers are usually smaller and not as palatable as those that have been bred and grown exclusively for their tuber.

I would wonder about any possible pesticide used by the greenhouse growers.
They can be used to start new plants, they root easily.
Never tasted them...Rina