That was my first modern mechanical keyboard. It's very heavy, solid, feels well built. I've no doubt I could've used it for many years if I hadn't discovered Topre 
So what's the deal with Topre? Why does everyone like them so much?
Personally, I find the Topre switch has a
great feel. All the resistance is at the top of the stroke, and it falls down to the bottom in a way that I find very clean and satisfying. The HHKB also has the switches mounted the case, which gives it a lot of "give" when you bottom out -- and it also has really great PBT keycaps that contribute to the sound and feel.
side rant: It's a damn shame it's so hard to just try out a variety of these things before one makes a purchase. After doing all my initial reading and research on this site, I went for my first mechanical keyboard with the big mainstream (Cherry brown) choice at the beginning and liked it OK. But then I found I liked Topre more, and to me the feel (and sound) of Cherry switches just seemed kind of rough and scratchy after that. But then again, some people will just hate Topre and love some specific type of Cherry switch, or buckling spring, or whatever. So it turns into this rather expensive trial-and-error process.
