Jeff, thats a good question of which I have no solid answer.
I've used grease, Tri-Flow, and Phil Wood Tenacious oil in the past. Theres no reason your current chain lube cant be used. The only problem is that you may need alot of it to properly flush out the freehub. I doubt you want to use half a bottle of $6 lube. Tri-Flow is realtively in-expensive. Some synthetic Mobil 1 would work well.