A slightly longer range version of the gauss vomit expected on these beasts. Considering the low amount of energy hardpoints compared to the 5B, it's best to try and use those optimally for big boi weapons. Therefore here's a pretty standard gaussvom build to play when you want something different from dual HGR on these chassis.
As the -5 looks pretty underwhelming (read: undergunned) with just 2x HGR + 3x ERML something like this probably is the was to go to mount weapons worth in an assault mech.
Fixed in this evening's hotfix. I might give this build a try though: the HGR works well but if you get your hits right, but the damage numbers are underwhelming there (though they can rack up kills if you make your shots right).