Neither of which can turn...
did you read the article on the quad...it states it was only built for auto shows, not to ever be driven, a Concept in other words...and the Tomahawk was built as a Concept vehicle(to gauge how much people go "oooh and ahhhh" towards them at auto shows),and rarely ever to be produced...
but I agree, I wouldn't want to race up onto a sudden turn on either of them.