|
Bikes will end up lasting longer from their increased toughness and natural speed. They can perform the same function of the raptors, at about the same point cost; five raptors with two meltaguns come in at 115 points, and five bikes with two meltaguns come in at 130 points. If you were to make the raptors nurgle, they'd be even with the bikes at 130, but if you're dead-set on running iron warriors, you wont be able to mark them.
So it really does come down to preference on movement and tactics. The bikes will move faster across the board on any given turn, but cannot jump over obstacles or hide as easily. Likewise, they lack the deepstrike flavor of the raptors, which really should be used as such. Previously mentioned sacrifice tactics hold true, deepstrike them into a safe position, pop a piece of armor, and whatever else happens is a nice bonus.
Do not consider the warp talons. They just don't make sense in the vast majority of ways you want to use them, they're much more expensive without being equally more deadly/resilient, and while the models do look amazing, they really need a delivery system other than deep strike to be effective. An edition which sees a proliferation of heavy ranged firepower has no room for a purely dedicated melee unit; there's a reason we stopped using swords when guns were invented. If you decide you really want to try and make them work, you'll be better off picking up the Raptor Talon as an aux choice to let them charge on the same turn they deepstrike.
Best of luck!
|