Most keys on a single board I've had is 120, I used 1 of the extra 15 keys, and then only occassionally. Now I'm on my new Filco 88 key which is the ideal size for me most of the time, but sometimes (usually at work) I do need a 105 key,or in the future a seperate keypad. I know a guy that's on his 2nd or 3rd Corsair K90 through RMAs who says he couldn't cope without the macro key mess at the side.