Opinions opinions opinions... I like the tiny size of the HHKB. The feel of the Topre keys is okay, but IMHO Cherry Blues are the best currently available in a reasonable size board. I need to try a Poker or a poopoo (what is it called again? nopoo? nupoo?) One thing that might cause you trouble with the HHKB is the backspace, ~, and /, but if it's your primary keyboard I'm sure you can get used to them. It takes me about 5 minutes to recover from changing between HHKB and my other boards.
If you are dead set on Topres, as I was, get a HHKB. If you end up loving the feel, but hating the layout, you can certainly resell it and get a Realforce. If you hate the feel, but love the form factor, you'll know where to go from there. If you love the feel and love the layout, you just saved $1000s! :-)