I've liked both names for quite some time. I used to like the
MacKenzie spelling, but now I think the random capital letter looks strange and I prefer
Mackenzie. Also, I really only like
Mackenzie on a boy now. It used to be one of my top choices for a girl, but now I don't really care for it on a girl. It's not even the "son of" part, I just think it's better on a boy.
Makenna on the other hand, I only like on a girl. I used to like the
Mckenna spelling, but now I prefer the
Makenna spelling as Mackenna and
Mckenna just look odd to me.