The two aren't even close. Pecking away works on iPhone, but is disastrous on my N1. I don't know if its touch screen sensitivity, a more narrow screen, terrible substitutions that require much more editing after the pecking is done, or a combination of all those things, but the experience is so much more inferior on my N1.
I just emailed the BK dev to see if he accepts suggestions or not, and landscape is more tolerable, but even typing this post was a terrible experience for me.
I have the benefit of having used an iphone for two years and still having access to a 3gs. This isn't a preference thing. One is obviously better, though I'm off to try swipe. *crosses fingers*
Edit: I'm using swype right now and I'm impressed. Let's see how it holds up over time. Typing this was effortless.