'I use them when the style is custom made for the song'
That's exactly my point Bernie - there are loads and loads of style files that enable real live playing which are custom made for the song (many many songs in fact) - and even Midis can be converted into style files so that you can actually play the song live with both hands...
A midi is useful when you are playing another instrument at the same time - otherwise you tend to run out of hands (and feet!)
Rog