I had the "dual" mirrors on my '06. Not bad and the convex portion helps a lot, but since I tow fairly frequently I ended up going with the Ford factory tow mirrors. The top, flat mirror surface is power, and the convex portion is manually adjustable. I still have the "dual" mirrors somewhere if you're interested. Let me know and I'll make sure they're still in good condition, I'll send you some pics, and I'll make you a good deal.
It wasn't too hard to swap mirrors, but it does require taking off the door panel to connect the power mirror connector.
SMB-less as of 02/04/2012. Our savings account is richer, but our adventures are poorer.