I use MacVim. MacVim is more integrated with your Operating system.
Some of the advantages of MacVim :
- If you open Vim inside iTerm, iTerm will catch all the Command key events. So, You can't set shortcuts with Cmd key for vim commands. In MacVim, You can setup shortcuts for Command key also.
- Mouse scroll will work in MacVim.
- You can use GUI to customise the UI