I used Eclipse, Netbeans and Idea, even Visual Studio (old versions) and don't remember using F-keys. F-keys were heavily used in DOS era, but later not much.

I used Eclipse, Netbeans and Idea, even Visual Studio (old versions) and don't remember using F-keys. F-keys were heavily used in DOS era, but later not much. Modifier keys are even more heavily used in Emacs than these IDEs. You will probably be more productive in all these eclipses with HHKB than with full-size PC keyboard because mouse will be closer to right hand home row position, and you can't avoid mouse with these IDEs. When Apple removed F-keys row on Macbooks, everyone missed only Esc key which was on that row, almost no one complained about removed F-keys. And AFAIK you can't press these keys with Fn+numbers on Macbook.