went for the white open coils in the end.
the main reason was i fancied something different, i agree with everyone it looks a bit better with the covers on. the open white looks very early 80s modified - as fernando said in his post.
i took out the jap enclosed switch as well and replaced it with a nice switchcraft item. i've also lowered the stop tail right to the body - nice improvement in sustain! i'll wait to see if i get more string breakages