I only ever got the Tool for 10 US dollars in sales, and that’s how I got all three that I ever bought (one Cree, my first, and two CRI, one for me and one for a friend). Usually the price I see is around 15. If you wait for this end of the year, Banggood or Gearbest should have them at a discount.
Otherwise, I guess the F3 is a good option? I have no experience with it.
EDIT: XP-G2 version is on for 12 bucks on Banggood right now!