In reply to the sheep:
I find compression tops best, as they don't really move, so are not rubbing back and forward over the nips. Short sleeve ones in summer, and long sleeve in winter.
But as said above, it only affects me on long runs, and I'm normally wearing a vest hydration pack which prevents most movement of baselayer.
On a warm day, when doing a marathon with just a club vest, then micropore tape.