It's been doing OK for me so far. It's reasonably common and offers a nice blend of range, OP cost and efficiency in the M ballistic slot. I particularly like the 800 range without additional investment into Ballistic Rangefinder on ships that have a bunch of M ballistics. I also much prefer it to the Arbalest Autocannon as early-game M ballistic kinetic damage.
However, an issue remains that if I am using M ballistics for shield damage, where am I getting my HE? Needs to be matched with an efficient torpedo on things like the Enforcer, or paired with an escort/big brother that offers HE damage. If I'm using Heavy Maulers (which I have a hard time finding in the early game) then I mostly want to range-match with HVDs anyway.
It also looks like we have a clear progression of some kinetic ballistic lines now
Railgun line: Railgun-->HVD-->Gauss - long range, high accuracy, low DPS, low efficiency, rare
Needler line: Light Needler-->heavy needler-->storm needler - good accuracy, high DPS, medium range, OP expensive, rare
Autocannon line: Light AC-->HAC-->Mark IX (?) - not sure if Mark IX goes here. This seems to be the middle of the road for kinetic ballistics, with medium-to-longer ranges, medium-to-poor accuracy, medium efficiency, and quite common.
The machine guns are point defense. No idea where the Arbalest AC fits in. Doesn't seem similar to LAC/HAC.