The first thing I would ask is what do you need the tool to do,... if your trying to turn nuts and bolts you wouldn't buy a hammer and so on you get the idea....
Are you looking for a target rifle with a little more punch then the 22,... I really like my little 22 hornet it will take groundhogs at 150 yards all day long, and the cost of ammo isn't that bad.
Another thing to think about is the cost of ammo, if you cant afford to shoot it you'll never be very good with it for lack of practice.
One more thing to consider is recoil if your unconvertible shooting it you'll never shoot it well, I'm a firm believer in one well placed shot is better then 50 just scattered out there not that there are times that cover fire would be necessary, but I duet you'll need it, although it's fun sometimes just to hear it go bang.......
Personally I have at least 1 of just about everything in the gun department and my newest favorite is the Saiga 12 as that I have automatic loaders for 12ga cost is acceptable and you can shoot it semi or full auto and let me tell you a 12ga at full auto is a blast to shoot, for a close rang battle weapon this is the best I've ever seen, All it is is a big AK47 chambered for 12ga, simple and controllable very very good gun.
So like I said, what would you like the gun to do...?