I bought one on sale for 500 total price. I love it. I probably shoot this pistol the best out of my entire collection. It fits my hand perfect. I have large hands, but mostly long fingers. I have the one with the normal glock rail.
How big was the 21 for your hands. if not much bigger i would get it right away. IMO its the best gun Glock makes.
I also find that the grip angle of this one is slightly different from other Glocks. its more normal 1911 like, but not by much.