Sorry, I should probably clarify my response focusing on the "next four years" portion of the equation:

Next year, I think Conacher may outperform Huberdeau, perhaps by something on the order of 10 points or so (attributable primarily to the quality of linemates that he'll likely be playing with compared to Hubs).

In two years, I could see the two giving roughly equal output, if not slightly in favor of Huberdeau.

Years three and four, I think Huberdeau really takes off and that's where having him over Conacher could pay big dividends. By then, he should be firmly established as the undisputed #1C and main offensive cog for the Panthers. And while Conacher's a fine player (have him on my roster so I hope he does well), he's no match to Huberdeau in terms of skill level and overall upside.

Both really good young players to potentially have on your roster. But in the latter half of your 4 year horizon, I think the higher skill level that Huberdeau brings to the table shines through and tips the scales pretty decidedly in his favor.

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14 Team H2H Dynasty League (14 keepers, 21-man roster, no farm)
G, A, PPP, SOG, BS, +/-, GAA, W, SV%

C: Giroux/B.Richards/Ennis/Cullen/Grigorenko
W: Ovechkin/Neal/Nash/Skinner/Eriksson/Silfverberg/Samuelsson(IR)
D: Doughty/Boyle/Faulk/Seabrook/Martin(IR)/Seidenberg/Brodin
G: Fleury/Markstrom/Lehner/Khudobin