"In response to the economic sanctions placed upon them by Enceladus Corp., Mars Power Industries has stopped importation of high-durability MPI Railgun parts to Enceladus Prime..."
As it stands, RG is a cheap, just as reliable, and extremely versatile upgrade to the standard Mass Driver... and all the other ones, too.
Its high volume of fire makes it optimal for combat and its relative inaccuracy becomes an advantage in rapidly breaking down ringroids. As a result it's the most effective kinetic weapon in both mining and combat applications, obtained at a negligible price point to the default EMD-14.
To give other mass drivers room to breathe, RG should suffer from accelerated wear accumulation, reducing its durability in all but the lightest of dives without compromising its combat effectiveness or breaking the bank of fresh ringas.
Visual ablation "sparks" considerably increase in frequency and quantity.
RG's strong ammunition economy could also be reversed by increasing ammunition consumption per shot with an according decrease in velocity, but I appreciate the current variety.
"...Nakamura Dynamics has been working to pick up the slack, but the sudden overload of demand leaves their quality control considerably lacking."