In terms of raw ability, Haynes was the best player Parramatta has ever produced, imo - kick, pass, run, tackle...he could do it all.
But in a professional league, with a salary cap, I would take Gutherson over him; I'm well aware that he is nowhere near as talented, but Gutherson provides in areas that Hayne struggled in (leadership, involvement), costs a lot less (allowing us to spend cap money in other areas), and (while not being in the same league as Hayne) Gutherson is still a very skilful fullback.
I know it's controversial, but there you go.