If by modded gauss you mean the quad-shot gauss repeater, nope - the range is 1200 instead of 1500 so it requires better range control and also requires slightly better "stay-on-target" skill since the damage the normal gauss is doing in a single shot is now spread over a burst of 4 shots (but the main issue still remains the lower range)
and iirc they fixed the premium ammo bug that made those gauss repeaters so powerful using premium ammo and (in the past) allowed a sidewinder to kill a hydra.