I owned a Kanati (and passed it along when I just had to have more weight) and have a FireFly that will never leave my possession, and will be handed down to my children.
That's not to say that the Kanati wasn't fantastic - it was, so much so I really, really want to get another one - but it was nothing like my Firefly. The Kanati felt light in hand, swift and purposeful. The Firefly feels solid, sure, and full-gripped. To me they just felt very different, but both were outstanding.
I think you'll have a difficult time trying to find the feel of a one piece Kanati in a three piece take-down. You'd be better served looking at a 2 piece, something like a Shrew. The Shrew I had felt very similar to the Kanati, just a little more full in the grip (it had a leather wrap...)
Just my $.02 - there just too many great bows out there to even start chasing around...