I really like my stevens 200 in 22-250 for varmints.
It's easy to reload and it's versatile. Even with the slow twist of my barrel (1-12) I have developed some excellent loads with it. Actually I've found it hard to find a load that doesn't shoot well if you tailor the bullet weight to the barrel twist.
I have one load using bluedot powder and a 40 gr. sierra hp that runs around 2500fps with very little recoil and noise. It basically turns the gun into a 22 hornet.
My main load runs around 3300 fps with a 50 gr. blitz king and considering I'm using a box stock $350.00 gun is rediculously accurate. It's average group size is .5 moa or so out to 200yards (as far a my range goes) and has taken gophers, foxes, and coyotes farther than that.
Also for fun I tried to crank the most velocity I could out of it at around 3800 fps out of the stock 22'' barrel with no pressure signs. I know of another person using the same load in a 28'' barreled gun who gets 4250fps. This load doesn't exceed any manual's maximum loads either.
Not to many other commercial cartridges are pushing rounds much faster than that.
I also like that ammo and reloading components are cheap and widely available. Not as cheap as the .223 but close.
It's by no means the be all end all for varminting but I really like it.