Mmmm... Quad bus-guns...Mmmm... %D

Dual-rail is pretty good... Just back up in physics mode and the rockets will rarely hit you. However, it takes a lot of rail shots to kill a valk.

less than 10 hits, and you've got 60 shots.

Not all of them hit though. And there is the long cooldown and energy requirements. It takes quite a bit of time to fire all those shots.