I was most disappointed by how much friction topre had..
The HHKB has way more friction than the Realforce boards. I was really disappointed by it when I got my first HHKB.
Something else strange is that the black keys sound and feel better on both the Realforce and HHKB (I have both colours of each).
The Realforce is just a better keyboard all around. The HHKB, while I really enjoy it in its own way, is really inconvenient a lot of the time. It's fine for general computer use, but anything that uses the F-layer or lots of navigation is a pain. The 45g in the HHKB is a bit heavier and pops a bit more than the 45g in the Realforce, though.
I do find that I get sick of all my keyboards before long, whether it's boredom, inconvenience, size, sound, weighting... it's always something. I praise the Realforce 87U 45g as much as I do because it's the only keyboard in my signature that I don't really tire of.