It really depends on how big of a hand that you have. I am 6'3", so I have fairly long fingers. I have both the 20 and the SF. The 20 is a good handful, but not difficult to shoot and control, for me, grip wise. The SF does fit a little nicer though. If you are getting a bargain on a used 20 and it fits then go for it. Otherwise, I would have your FFL order you a 20SF. My wife and daughter shoot the SF without difficulties, so you might want to consider who would be shooting it besides yourself. The 10mm is a wonderful cartridge.