I love Evans as a defender hustle guy. I would replace him with BBD without even thinking. Of all the undersized bigs in the league, Evans is my favorite. Offense or no offense.
I guess then it's good that the people who do the replacing also do the thinking?

For starters, Davis is a better defender and a better hustler than Evans.
Sure, Evans is a pretty good rebounder. The problem is, he doesn't have any other NBA skill that's even mediocre. He doesn't have great size, doesn't have defensive skill, and he takes the concept of "stone hands" to a whole new level. Not to mention that he's coming back from a major injury.
Reggie Evans at the veteran minimum to fill out the roster? Maybe, if nothing better comes along? Evans as a replacement of Glen Davis ? No way.