I know about Evans. As a Sonic fan I watched his surprise rookie exhibition season. The undrafted sensation made the team, kept improving, and lasted 3 years under McMillan, becoming a starter at the end of that period, as I abandoned the team and switched allegiance to the Blazers. He weighs a lot more now.
At the low sub forward spot, a specialist like Evans is better than a generalist like Craig Smith. The guy will be inserted into only certain situations, and not play across a spectrum of situations throughout the game. So it's better that he be great at 1 thing and lousy at the rest, than he be satisfactory at everything, more rounded like Smith.
At the 4th forward (after Aldridge, Wallace, Batum), Evans would have helped us more. If 2 forwards get injured and the 4th guy has to start, then Smith is better. But for the expected niche at 4th forward, Evans would contribute more in selective minutes.