[nate00]

I was also unable to switch until I forced myself to go cold turkey. Putting this into your vimrc will disable the arrow keys

  noremap <up> <nop>
  noremap <down> <nop>
  noremap <left> <nop>
  noremap <right> <nop>
  inoremap <up> <nop>
  inoremap <down> <nop>
  inoremap <left> <nop>
  inoremap <right> <nop>

It's extremely painful for the first day or two, but it's worth it. (Starting on a weekend might be a good idea.)