I have a 9mm, a .357sig, and a .40sw. And honestly, I feel that the difference in recoil between the three of them is pretty negligible. Maybe this is the case for you, maybe not. I shoot and handle all the about as well and I'm a relatively inexperienced shooter.
9mm and 40sw are both pretty economical rounds. I get 9mm practice rounds for about $10/per 50, and 40sw for $12-15/50. Defense rounds cost the same for either, about $20-40/50, depending on your preference. The .40 is the more lethal round, while the 9mm offers a magazine capacity about 30% greater. In poly guns especially, I'd imagine follow-up shots are easier to place with the 9.
This much is true: They're both adequate defense rounds. They're both affordable, and generally easy to find. In that sense, they're good "value" rounds. It really does boil down to your own preference. I like the .40sw for a home defense gun, but wouldn't balk at the 9mm for a moment.