I've heard plenty of "well seasoned" outdoorsmen say that a .22 Magnum is underestimated and 22 practice ammo is cheap.
This is one "well seasoned" outdoorsman who will tell you the .22M is OVERESTIMATED. A .22lr rifle is a squirrel and bunny gun, a .22m handgun is about equal to that. So using simple deduction a .22M is a squirrel and bunny gun. Now that's not all bad, I like squirrel and bunny guns. But if I'm gonna shoot a squirrel and bunny gun it's gonna be a cheaper, less noisy .22lr handgun. If ya need something bigger, you need something bigger, not something equal to a .22 rifle.
BTW, if an SP was outta my price range (and for the most part it is) I'd look very very hard at the Charter Arms lineup.