One of my lawyers taught me that rule - Use OPM - Other People's Money. He was a master at it - that is why I fired him.
The challenge with Europe is that the economies are still growing which means that there could still be upside. The European index is dominated by banks and financials and manufacturing. When interest rates rise, banks will do better. If the US Dollar story is right Europe manufacturing will benefit from a weakening Euro. I would be holding back some to grab that advantage. This is what I am doing in my overall portfolios.