Along the same lines is the Wasp 1W. Six SL on a bug sounds like a joke, until you consider A) no one really cares about bugs when there are far bigger threats out there and B) a potential of 18 damage to a rear arc plus, depending on terrain, kick or charge damage since the SLs are all in the arm and torsos. And it's really cheap BV wise so it costs nothing to put in a good gunner.
Along the same lines is a favorite of mind: the Dasher H. Nine HSL is a whopping 54 potential damage plus kick or charge damage. Again, it's fairly cheap so it's not a huge cost to put in a hot gunner.