I have a five month old 87U variable silent, a one month old HHKB Pro 2 (non-silent) 45g uniform, and a two week old 87U 55g uniform. I can't comment on the feel between the variable silent and variable standard because I don't own both.
The key travel is the same for silent and non-silent switches, which means they've engineered the switch housing to accommodate the silencing material. The silent switches can be identified by their purple switch housing. Reference here for switch pictures and more info:
http://deskthority.net/wiki/Topre_switchI thoroughly enjoy all three keyboards. These are my 'personal' preferences and observations. I emphasize personal preferences because they are completely subjective. Somebody else will have other preferences and neither is wrong. It's like asking which color car is better.
87U variable silent:
Reference here for the key weighting:
http://i.imgur.com/X6g6Y.jpg. Pinky keys are 30g for the US version. It's interesting to note that the modifier keys are 45g, not 30g. The 87U variable takes some getting used to because it's so light. That's not necessarily a bad thing. But it took me about a week to adjust coming from MX browns. I kept bottoming out too hard. But once I modified my typing style, it was effortless to type on. And yes, it is extremely quiet. I can be on the phone with clients taking notes and they can't hear me typing, which was what I was looking for. If I had a complaint, I'd say the switches are on the light side when typing fast. If you're taking your time, it's great. If you're pushing for speed, they're a bit light.
HHKB Pro 2 non-silent:
I love and hate the layout, all at the same time. The idea of a compact is that you can type everything without your hands leaving home row. If I dedicated a lot of time to getting the layout down, I think I could actually work faster for this reason. But I struggle with the arrow keys being on the second layer, and as a coder, I rely on my arrow keys constantly. I do like the 45g switches. However, understand that Topre switches have a break-in period. I'd say at least two weeks as your daily driver before they settle in to their 'final' key weight. This is important to remember.
The switches are PCB mounted on the HHKB, which does change the feel of the Topre switch. Some prefer the key feel on the HHKB because of this. Personally, I'll take a plate mounted Topre board over PCB mounted any day. Do I want to get rid of my HHKB? Not at all! It's a nice change and a joy to use, especially for relaxing and banging out some emails.
EDIT: I've been corrected. The HHKB Topre switches are not PCB mounted. The upper housing that holds the switches is molded as one piece. Daerid used the term "case-mounted", which seems to be the most accurate term.87U 55g uniform:
I never would've considered this board had it not been for the guys on GH preaching the 55g gospel. But, I had the extra money, so I ordered one, primarily out of curiosity. I figured I could sell it on GH for a minimal loss if I didn't like it.
Three days into using it, I almost put it up for sale. It was too stiff for my taste. But, understanding the Topre break-in, I decided to stick it out. I'm glad I did. It's been my daily driver for two weeks now, and the keys have lightened up to what I consider perfect. I know it's not increased finger strength because I can switch back to my variable without problem. The key weighting on the 55g lightened up to a larger degree than the other Topre switches.
I am extremely happy with all three keyboards. But if I could only choose one, it would be the 87U 55g uniform.
Don't let all this frustrate you. Any of these Topre boards are so far above anything Cherry MX, it's almost laughable. Regardless of which you choose, you'll be happy with it.
