I found one of these pretty things for sale, I may pull the trigger on it.
The Buckmark is a great choice. It is a very proven design.
If you get anything in 22, I would get one that is dedicated and built upon that round. If you get the Walther P22 or Sig Mosquito, you run the chance of buying one that is extremely ammo sensitive, as others have said. I have heard bad things about shooting bulk ammo through P22s and Mosquitoes, and if I had to take a shot in the dark (pun intended) I would say that will be the bulk (zing!) of what you run through it.
Go with the Buckmark or a Ruger 22/45 and you will not be upset. Both will run all day long on the crappiest bulk ammo you can find and both are very accurate.