This gets my vote, although i haven't tried some of the finer 3m stuff.

Menzerna Power Finish with a medium pad on rotary has plenty cut to remove 90% of swirls and scratches, and finishes nicely enough to need no refining. Perfect for those kind of cars that you think actually NEED doing

Sonus do some good stuff too, more oily than the Menzerna so ideal if you need to work it a little longer for better shine, buffs off easily enough too.