In vim, you can still move the cursor around when in insert mode. It just isn't that functional and after a while you realize it rather is a beginner's mistake. Anyway, those modes aren't totally separated from each other. There also are shortcuts to quickly do something in another mode.

Having used emacs and vim for several years, I now am in favour of vim's editing modes. The only thing I don't like about it is the column numbering at the first or last position of the line (a problem you become only aware of when developing plugins though).