Another vote for G-Force here. A Banshee axle is a nice upgrade, but it is no stronger than the bent stock axle you are trying to replace. I'm not saying you're gonna bend it (They're sturdy enough for all but the biggest, frame-cracking jumps), but I'd go ahead and go aftermarket. I like the G-Force axle's clever lock nut.
Never have to mess with trying to tighten two factory-style jam nuts at the same time again. Plus the G-Force axle's lock nut comes with the axle when you buy it. Don't have to go out and buy an axle PLUS the nut you need. I've given a G-Force axle in my old Warrior hell and never had trouble with it. The nut never came loose and I did all I could to bend it with no luck. You can get a G-Force shipped to you for under $ 200.00, and they install with no more effort than a 'Shee axle. Its actually easier, IMO.