If I was gonna sell the SL, I wouldn't go Evo, I'd go Proto.
IMO, the Proto pretty much makes the SL obsolete. I'm not sure why anyone would go SL > Proto if buying new. NS is wise to keep it around as it's been their most popular board, but from an objective standpoint, there's really no reason to pick it over the Proto.
IMO, the NS portfolio is starting to get pretty crowded. If I was a one board guy, for the way I primarily ride, I'd be struggling to choose between the Proto, Cobra, and Heritage. I could make a strong argument for all of them, but I'd probably end up going Cobra. Not sure what the hell that had to do with this thread. Sorry for rambling.