I Use MSN as my browser home page.
I allow Microsoft to send me promotional messages.
All in all, it works as a reasonably good spam trap.
I empty junk at least twice a day, but scan the headings to be sure that nothing got trapped that shouldn't have been.
Today there was one in there - from Microsoft - advertising their upgraded Hotmail.
I'm not sure how good the product is, but I know that the spam trap already works pretty effectively.