Polanco and Manny for BJ Upton?

A manager in my baseball league is attempting to trade me Placido Polanco and Manny Ramirez for BJ Upton. BJ is one of my main SB guys next to Reyes and Ellsbury, so that category would be weakened, but I could use some more HR to go along with Morneau and Beltran. Should I do this trade?