Also, do you care if it has buckes/clips or do you prefer it to tie?
I have a Beco 4th Generation. I have a small build and so long as I have the chest clip done, I've never had had problems with it slipping off my shoulders. (That may be a thing for you for any SCC) IMO, the butterfly is really fussy. I have never had the need to pass the baby off while wearing and I'm really confident getting a kid on my back, so the extra buckles are just a bother to me, I can totally see their appeal to others though. The 4th gen you can probably find a lot cheaper since they've been around longer. My 6'2" 300#+ DH has been able to use the Beco without even a waist extender (though he probalby would have been more comfortable with one!)
Another really pretty option in the same style as the Beco is the Connecta.