Last year Mason was pretty productive for the Ravens, despite turning 37 in January. Mason managed seven touchdowns and over 800 yards in 2010, but it was the first year since 2006 that he did not go over 1,000 yards.
Obviously the Ravens were turned off by Mason's age in this scenario.
Evans is definitely more of a deep threat than Mason, but is he an upgrade?
In his seven year NFL career Evans has only had two 1,000 yard seasons, and last year only had 578 yards and four touchdowns.
The thing that has to be evaluated here is that Evans and Mason are two different type of receivers. Evans is obviously being brought in to help spread the field for Anquan Boldin, something that Mason wasn't capable of doing.
Evans over his career has averaged 15.7 yards a reception, compared to 12.9 yards a reception for Mason.
While Evans probably isn't a better wide receiver than Mason, he is what the Ravens needed, and what the Ravens got.
Giving up a fourth round pick when you know what you're getting isn't an awful deal, but it isn't ideal either. However, the Ravens missed out on several free agent opportunities this offseason and put themselves in a bad situation.