I have to air this: I received my 45g Topre and it feels great! I missed the feel of this switch. But the 55g was too much for me. The 45g is heavier than Cherry's 45g MX Red, which really suits me--and addictive for those of us who prefer Topre to other key switches (+1 for me on this score). One cannot compare the two, only contrast them. I understand the force curves are different for these 45-gram switches. I can see why you sold your Cherry keyboards. I may have to get another 45g 87UB--for me, like the 55g for you, feels exceptional and is all one might ask for in key switch and keyboard. Also, my touch-typing accuracy has vastly improved, in this short time, with the 87UB. It's just the best for me.
The guy I sold my 55g to may not want to keep it. His first impression is that it was really heavy. I know he's a fan of HHKBs. If you want, you may be able to make trade with him. If you're interested, PM me and I'll give you the information.
We don't have to keep secrets... its me

And yes - it certainly is stiffer than my HHKB - but I'm not sure its a bad thing... I just can't say after 1 day if I would mod my HHKB (which actually was my original intention - but this keyboard is so beautiful - how could I do it to it!

)
Anyways, I'll report back in a week which way I'm going to go... right now I have a tri-fecta... I have the HHKB Pro 2, the FC660C, and now the 55g RF 87U. I really want to stick with 1 style keyboard if I can - because one things for sure.. going back and forth between layouts isn't efficient... you spend a lot of time adjusting.
And I got work to do - ya know! Just like I want to learn a new keyboard layout.. Colemak, or Minimak-12, but I just can sacrifice the time to drop 30 WPM on my QWERTY skills while I'm learning it.
Although it isn't all about WPM's is it? Its about comfort - what you like.. that kind of thing. (not that I would mind typing 100WPM's on a board!)
Oh yeah... i have an ErgoDox kit coming tomorrow too.. now I have to find the time to build that... I've never soldered a diode in my life lol! (I'm a software guy - not a hardware one LOL)
Peace.