Range-wise, SB Gauss pairs well with regular Gauss, ER PPCs, ER Large, and LRMs. It’s easy to drop one in, say, a Falconer for a 5/8 platform. (Or in many slower platforms like the Cerberus, Gunslinger, Nightstar, Pillager, or T-Hawk.)
The tough part is giving up the headcapper for the crit-seeker. That, and the limited pool of sometimes inexperienced designers that the TROs/RGs pull from, is why the SB Gauss has not been more popular. Logically, at a minimum, each of the units above would have an SB Gauss variant (probably deployed at a 1:3 ratio) for dealing with combat vehicles, airborne units, and achieving kill thresholds on BA.