So EliteKeyboards is vociferous in proclaiming on its product page that you can't use the HHKB blank keycaps on a Realforce. I understand that a single set wouldn't provide enough keys (because there is no separate function row, etc), but if I bought two sets of blank HHKB keycaps, wouldn't that give me enough to fit every single key on a Realforce 87U? Or are some of the caps different sizes? What's the deal? I basically want to get all-blank black keycaps on an 87U.