most unexpected part of using a wireless keyboard/mouse combo is that i cant set my phone on my desk anymore because i guess the wifi and cell signal and bluetooth all screw with the 2.4GHz signal between the keyboard/mouse and their respective USB receivers. the effect is immediate, noticeable, and extreme. Keyboard will be typing fine, then I set my phone down in the path of the keyboard and receiver, and immediately, keystrokes start missing, lagging, or repeating, sentences chop and scramble as I type them. Pick my phone up again, all return to normal.
My next keyboard, at least, will be wired. Seems to me wired keyboard / wireless mouse is about the best setup. since the keyboard doesn't really need to move, but the mouse's whole thing is moving freely.