While I think that user is overvaluing him here. I can say that Calgary would not move him for less than a 1st. Pospisil's playstyle is very desirable to a lot of teams and at a dirt cheap cap hit for both this year and next Calgary certainly won't be selling low on him. Especially if he can transition to full time center.
Beck Malenstyn would be my comp to throw out for a physical, bottom 6 forward in his mid 20s
I'd throw out Cotter as wellbut since that was a player for player type it's tougher to estimate, although I imagine it was again similar to the Malenstyn price
People underestimate the impact (positive or negative) that penalties can have. Pospisil had the worst penalty differential rate among forwards last year due to his 3 major penalties (Deslaurier I think may have been worse but I always set my minutes cutoff at 500 and deslaurier was just short).