I just posted a humorous rant about 55g vs 45g Topre recently: https://geekhack.org/index.php?topic=67186
I agree that the Leopold FC660C is a very special keyboard. I love the compact size (very portable), the intuitive Fn layer of the arrow keys, the quality of the keycaps (which I understand is a vast improvement over the earlier version's keycaps). When I type on the FC660C, the keycaps gives off the impression that they're made of some expensive hard-wood instead of plastic. I'm not sure why I get that impression. I don't get that impression when typing on my RealForce 87U keyboards.
Out of my three Topre keyboards, the Leopold is my favorite. But there's one thing I dislike about it, and that is the micro-USB cable. I don't think it's wise to use a flimsy connector like that. I would have preferred the plug to be under the keyboard, and have cable routing channels like the ones on the RealForce keyboards. If you look at the way the cable is connected under the keyboard on the 87U, you can see there's enough room for a micro USB plug like the one FC660C uses, and that's what Leopold should have done IMO.
My other two Topres are the RealForce 87U Type-S ergonomic weighted, and 55g uniform weighted.
The Type-S is very quiet--the most quiet keyboard I have. It feels significantly softer to type on due to the weighting, and I think it's good for those who dislike heavy keys, or during times when you're not feeling well (sick, tired, headache, feeling weak, etc). Although it's only the pinky keys that are lighter weight, the overall typing experience feels about 25~30% softer than the 45g FC660C. For people who love tactile keys, it is definitely not tactile enough. Those who lover soft/smooth keys will love it, I think.
The 55g version is about 15~20% more tactile than the 45g version. It's not "night and day" as some people claim, so if you are considering spending your hard-earned money on a 55g because everyone is telling you how it is the best Topre and how it is a "completely different experience" from the 45g, you need to think twice because the difference is not as dramatic as that.
I read your referenced thread, in addition to your 'expert' opinions expressed here. While everyone is entitle to their opinion, yours simply isn't accurate. But of course, you're an 'arteest'. You might try taking a break from painting and use a keyboard for 12 hours per day.
There are those who drive to 7-Eleven for beer, and there are those who drive for a living. The former won't notice much difference in their seat. The latter will tell you the seat is everything.
If you work on a keyboard every day, all day, the subtle differences you've so opinionatedly pointed out, become quite important. If the differences aren't that obvious to you, then you are wasting money on Topre boards. Save your money and just buy a nice MX board and you'll be happy.
The humor here isn't that some in the GH community have strong opinions regarding keyboards, which might seem anal to a normal computer user. The real humor here is people who espouse strong opinions about a topic of which they obviously know nothing about.