The nerf vulcan or the nerf swarmfire?

I like the nerf vulcan because its like a turret type gun and it shoots a little faster. Im getting them both, i just wanna know which i should get first? There both semi-auto, they both take 6c batteries and there both have some weight to them (not lightweight), which isn't really a problem for me because i like heavier guns, it gives them a more real feel. Then again 8 pounds isn't really that heavy but anyways, which nerf gun should i get first???