a .22 is a good caliber for an all purpose gun. cheap to shoot, fun to shoot and you can actually use it for alot of things (hunting, home defense)
i have a semi auto savage F64 (?, i think that's the model). it has a 20" bull barrel on it and holds a 10 round clip. i have 5 or 6 clips for it. fun as hell to shoot. i buy 550 round bricks from walmart for $18.xx.....got 4 bricks in the gun case right now. on a rest, i can shoot through the same hole over and over @ 25 yards. it holds about a 3 inch group @ 50 yards and maybe a foot @ 100 yards. not bad for being semi auto. best thing is that it was only $160 out the door brand new. i've easily put 40,000 rounds through, it's all still original and functions flawlessly (as long as i use its favorite ammo, otherwise the bolt wont cycle properly)
the best part is you can kill something with it fairly easy, it's pretty quiet (compared to other calibers) and there's pretty much no recoil. if someone were to break into my house during the night, half asleep i could easily empty all 10 rounds into them. i dont care how small the bullet is, 10 of those will put quite a hitch in your giddy-up.
also, i think a lot of people forget that the M16 (and most of the variants -AR15, M4, etc.) was designed to use what is pretty much a .22 cal bullet. it just has a larger shell and uses more powder.
$250 sounds like a pretty damn good deal, get it. i'm actually about to make a new gun purchase myself, gettin a handgun with my tax return.