I visited Leaderskey shop in Korea with the sole purpose of wanting to try the Topre switches and knew pretty sure I wanted the 55g but wanted to make sure by trying it out in person because why not, the store is not too far. Does it live up to the hype? Oh yes it does..
I went back and forth trying RF 55g, RF 45g, RF 45g variable, RF 45g silent and Leopold FC660C 45g for a little over an hour in the shop until I was confident in my choice.
At first what struck me odd was the difference in a well used Leopold FC660C and a nearly new sample. A fairly new Leopold FC660C felt almost as stiff and crisp as the very well used RF 55g. Initially I actually was second guessing whether the Leopold FC660C would be better for me. It felt tight, satisfying, and crisper than expected.
But after about 45 minutes of going back and forth the very well worn RF 55g is slightly more tactile, focused, solid and not a HINT of the spongy feel.
The well worn Leopold FC660C was actually very sloppy, It reminded me of typing on my 7 year old Filco MX Browns with the shiny key caps. The solid crisp break at the top of the key wasn't there like the 55g and I can feel the spongy bottom dissipation in my finger tips. It also had the broken mini-USB which seems like a common weak point.
The RF 45g I have tried a coworkers before and did not impress me then and did not impress me in the store at all. Again, the solid feeling of what I can describe as breaking the top surface tension of a water bubble of the 55g wasn't there. Easy pass every time I came around to it.
The RF 45g variables caught me off guard. I thought the outer keys where my pinky was hitting was broken. Like the rubber dome has collapsed, like a jelly MX black. Felt like my pinky fingers were falling off the edge like walking along a balance beam. When you play the piano "chopsticks" song on the keyboard going inwards the outer keys have none of the qualities of the Topre I like - The solid tactile break of the pressure at the top of the key to a nice solid cushion bottom. The top feels vaguely linear with a very spongy bottom out. Not for me at all.
I was hitting 135 WPM on 10fastfingers with both the near new Leopold FC660C and the RF 55g effortlessly. Much improvement from having to wrestle with my old Filco MX Browns to hit that number. They are both a joy to type on but The RF 55g I would say has 5-10% advantage throughout all parts of the key travel. I am now typing on a brand new RF 55g which would probably widen that gap further.
I would break down the 55g key travel bits from the top part having a clean tactile pressure break that is solidly warm giving you a fuzzy feeling each keystroke transitioning into a very focused smooth travel down a fireman pole to dissipate on a nice plump air mattress personalized for your finger. With the 45g, I lose the tactile pressure break feel and the plump air mattress is a bit aired out with a bit of sponge substituted in. The solid construction of the Leopold FC660C helps alleviate this but the pressure break is still muted and not as prominent and I can still feel a bit of spongy bottom.
I had my doubts when people say that Cherry MX switches feel like sandpaper, and not as smooth or solid as the Topre but I totally get it now. I also tried MX Blacks, Browns, Reds and Blues next to the Topres - they are harsh, have a sense of sand swirling about the keys and plastics crashing into each other. Blues were ok to type on but noise was a bit jarring.
It was also a major bonus point that the keycaps had Korean Hangul printing on it. This will be my sole typing workhorse at the office. My MX Browns will be used for gaming as the slight travel before registering is still advantageous in jiggling A and D keys in FPS type games. PBT DSA keys hopefully will alleviate some of the sloppiness of my super old keycaps on the browns.
tl;dr - I have drank the Topre koolaid and it is delicious.