I spend more time in a command line environment that most of the people I know (this is not a competition, and if it were there wouldn’t be any winners), and I’m a bit fickle. I’ve been using Oh my ZSH for a while, with the agnoster theme. It’s pretty and highly functional.
However, being the fickle kind of guy I am I decied to try out Prezto. Prezto started out as a fork of Oh My ZSH, but quickly became its own thing. OMZ focuses on being easy for beginners where Prezto focuses on speed and power users.
I’ve only been using it for a day or two, and so far there isn’t a whole lot of difference between the two. Prezto may indeed be faster, but I doubt I would pass a double-blind study of it. Being less user friendly might not be the best move. I’ll continue to play around with it.