I often press:<Ctrl> V to go into visual block mode and highlight a columnhit <shift>-i (to insert at the beginning of the line), type a few things (at this point, I see my changes on the first line, but not any others). and then hit <Esc> to go back to normal mode. After I hit <Esc>, I see the stuff I inserted get put in each of the other lines. What I would like is to visually see my changes on each line, as I type, rather than only on the first line. Is that possible? Go into Visual Block, select a bunch of linesHit <Shift> iAdd some text - This is the part I'd like to be changed. I'd like for the spaces to be immediately visible on all lines, not just the first line.Hit Escape - Now the spaces are added on every line. I'd like for this to happen sooner. I know that I could have done what I did in this example with >>. I chose a simplified example to illustrate the thing I'd like to change. Thanks! 
Vim - Is there a way to get immediate visual feedback during Insert in Visual Block Mode?
vim;vi
Try adding this to your vimrc:nmap <buffer> <silent> <expr> <F12> InsertCol()imap <buffer> <silent> <expr> <F12> InsertCol()function! InsertCol()    let w:first_call = exists('w:first_call') ? 0 : 1    if w:first_call        startinsert    endif    try        let char = getchar()    catch /^Vim:Interrupt$/        let char = \<Esc>    endtry    if char == '^\d\+$' || type(char) == 0        let char = nr2char(char)    endif  It is the ascii code.    if char == \<Esc>        unlet w:first_call        return char    endif    redraw    if w:first_call        return char.\<Esc>gvA\<C-R>=Redraw()\<CR>\<F12>    else        return char.\<Esc>gvlA\<C-R>=Redraw()\<CR>\<F12>    endifendfunctionfunction! Redraw()    redraw    return ''endfunctionThen press Ctrl-vI as usual, and then press F12.  It will insert and show all lines changed for each keystroke.Note: The script would be better if pressing F12 would go into insert mode, instead of requiring you to press I each time.  Maybe the startinsert command in combination with vnoremap could do this.