I know nothing about it - but 99.99% certain it's a 4-stroke. Flying fish don't do 2-strokes in their cruisers.
I would eliminate the Hovpod from your list unless it's really inexpensive. The other 2 are far better. Also consider the Universal Renegade if you're looking for factory built turn-key craft. Go test drive the craft if they offer it (or pay to get trained in one if you've never driven a hovercraft).