The vanu don't have the best LMG's. The best LMG vanu have IMO is the pulsar LSW after having trialed each LMG and tried them out. The drawback of the pulsar LSW is the lack of attachments. It is a very good LMG and really only needs the 2x reflex scope and the foregrip. But futher enhancements are not possible. Which can limit its tactical application. I think if you consider not just the base weapon stats but how the weapon performs after making the optimal mod choices I think you'll find that the different LMG's are actually very well balanced.
I just bought the SVA-88 (after reading the forums) and added HV ammo, and I have to say it's as loud and has as much recoil as the Flare......and I think I now prefer the Pulsar LSW the most....it seems easier to keep it on people's heads (less recoil) and it drops people well... So out of the 5 HA guns I've got I like the Pulsar LSW most, Flare, SVA-88, Orion, Lasher, in that order.
I have the pulsar lsw on my VS HA and the orion is perfect if I could get two levels of laser. LSW lets me do that and stays close to especially with the larger mag. The reload times on the LMGs can be problematic.