I'm thinking about getting a .22 pistol to go along with the 10/22 rifle, since the ammo is so cheap and plentiful ;-). I have a relative with a lightly used 70's (my guess) Ruger MKI, it has the tapered barrel and some funky hand-conforming wood grips. Can I get some advice on the relative quality and value of this model vs a more recent vintage MKII or MKIII?