I'm an older guy who used to work as a writer/editor for decades. I've taken to writing novels. Just finished my first one the past December. Days writing last from morning into the evening. Nine-hour days are my shortest when writing; 12-hour days are close to my lengthiest days.
My typing speed varies from 65 to 100+ wpm: It really depends on how much of my subject I have set in my mind. I suppose when writing subject shortfalls, my speed may go down to 35 or so wpm.
My typing began using typewriters way back. And banging away on those old Remington mills all day, one managed to build considerable finger strength. Like I said, I'm an older guy. I've had 45-gram Topres on an 87U, two in fact, but sold them. I find them too light for me. I tend to hammer my key caps, a holdover from the old typewriter days.
I'm kind of intrigued by the HHKB; I've heard some say the 45g Topre switch feels different on the HHKB. I don't quite understand how they might feel different compared with an 87U; but I've never used one, so I really can't make a comparison. But I am really pleased with the 55-gram 87U board.
My hands tend to fatigue because of age. But I find 55g Topre switches to be something an age-equalizer for me. I had tried Cherry MX Red switches, and I found myself making too many accidental key actuations; same for MX Brown and Blue switches. Topre is the one switch that just works for me. I poked out a 485-page novel in five months, working day and night. And this doesn't take into account the 45 or so pages I killed. I used an SSK part of the time, but found my fingers fatigued after five or so hours of typing; then I'd go to the 55g 87U and continue writing for hours. The 87U/55g went from my second favorite KB to my number one keyboard. But, I still enjoy experimenting with KBs. By the way, I'm working on a second novel, a followup edition to the first one. I spent my life writing for others, not I get to do it for myself. I'm grateful to have the time to write for myself, I love writing.
I really enjoy using a good keyboard; and I'm grateful to have gotten into Topre switches. I'm appreciative for what I have. And I do enjoy keyboard talk on geekhack with others who are so interested in keyboard switches and performance. Forgive me if I've gone on ad nauseum.