I've seen two of these banjo's and played both.

I don't know if I've been unlucky, but the ones I've played have been a nightmare to tune. One touch and the tone sroings wildly in either direction. What's more, the pegs need to be pushed in to hold their tuning once they have been loosened and turned, during which process "sproing" they fly out of tune again.

Two heads would definitely be a minimum requirement.