What Vim features are missing in Emacs with Viper and Vimpulse?

Question

There are important features of Emacs which are missing in Vim, such as the comint mode, and there are no scripts/plugins which can replace them.

There are also benefits

Answer 1

Being a lover of emacs as an OS and vi as an input model, naturally I wanted to love viper. However within two seconds of using it I had to give it up: viper does not support C-[ as a substitute for the escape key–which is an essential shortcut for the most frequently used command in vi.