The 2x PPC have such a different position that it is hard to function nicely. >.< I would go for more DHS, and sit back if using this. This, with a bit more close range ability. Allows you to hurt more in mid/close range. If you want you can use ERLLas in the arm and keep the speed.
I am using a 300XL with an AMS, one more ton ammo and a little more armor. I do have a 320 so I might try your original build after more testing.