Gaunter is a fun card in general, not only when you win the bet and pick the card you want, like the op says.
But, for me, the most fun aspect of using Gaunter has to do with the Renew fad. I used him for a while in my NR deck, along with other golds that are not exactly mvps ( except Avalllac'h, but at least, if the opponent Renews him, i get 2 cards ). "So, you have nothing else to Renew but my Gaunter ( or Dijkstra )? Good luck with that". Haha!