Recently started using the chicklet one. The layout is ok, but not as good as the classic, for me, mainly because the home/end keys are harder to find and they are quite useful. Apart from that, it's not bad, although I preferred having a menu button on my thumb than a print screen button.

I preferred the feel slightly on the classic thinkpad keyboards, but these keys feel bigger in use which is nice too. Having the arrow keys separated slightly is a big win. So yeah, while I do slightly prefer the classic keyboard, I don't think there's much in it, and the underlighting is quite nice.