What are you planning to do with the pistol? If it is just range time, I would echo the calls to look at a Ruger MKIII. It is a far superior range pistol than either. (I dare say they set the standard for 22 range pistols.)
If you're planning on making it available for defensive work, of the two you listed, the Bersa would likely prove better. If that is the case, and you like the Walther P22, perhaps you should look at the
Walther PK380.