Go used. A G3 to either of those isn't that massive an upgrade to warrant $500. However, for that money you can get something like a G6R, Victory or Geo 2, which is about as good as it gets really. But from those two, Axe, far, far quieter and smoother, and near enough the same efficiency. Ergonomics and looks are crappy though, also it doesn't have the super sweet ass manual (in full colour) like the Etek has.
My limit is pretty much 500$ I really wanted to get a geo 2 but for 700+ it's way out of my range