Does anybody have both? I know that the new one uses 2 AA's instead of 3, and has some sort of new power management functionality that allows it to use less batteries. As I understand it, the keyboard goes to sleep and wakes up as soon as you hit a key. What I am wondering is, whether the new version exhibits any more or less input lag than the old version. I'm also curious if anyone has noticed any other differences. The reason for me asking is that I'm looking to pick one up, and the old version can be had for a bit less. Thanks.