I have one of these at work. I switched from the Ergo 4000 to this, and I like it quite a bit. (There's a Mac version, too.) No idea whether it's a crappy keyboard by Atwood's standards.
Beware: there are trade-offs. For the Mac keyboard, you'll want to map Caps Lock -> Ctrl. I don't know what's optimal for the PC keyboard; I run Linux and don't use the Windows key.
Also, neither has a numeric keypad. There's a Numlock key, a la laptop keyboards. I don't miss it but some people do swear by them.
I'm assuming you've also ruled out Kinesis. :) I'm too scared to splurge on one but I've heard they're fantastic.
Anyone know why we see so few mechanical ergos? I would think keyboard snobs would be wary of RSI...
No idea why there aren't many mechanical ergonomic boards, though. I'm actually surprised by the extent to which people type on regular keyboards.
That mapping alone makes learning Emacs bindings worth it. Most editors can be configured to honor them.
I wrote a post about it recently: http://semmyfun.blogspot.com/2010/10/my-config-secrets.html