I really like Kaytee clean and cosy for several reasons; it's less expensive than carefresh, as Oreo mentioned, it expands a lot more out of the packaging than carefresh (so I guess it's even more less expensive than carefresh?) It's softer, I haven't had any issues with dusty bedding... and Cadmium noticeably prefers it. One cage set up I did recently had a deep area of substrate for digging (almost to the top of the cage: she *loves* to dig) but because that side was carefresh and the rest was Kaytee, she pretty much refused to use it
I certainly can't accuse her of being wishy washy or not knowing what she wants :P