Yeah you're in trouble if one has it charged. Suppressor grenade helps but I usually run a fusion and scout rifle, and if I see someone charging I try to blast them with the fusion before they get too close (you get to charge nice and safe in your bubble). If they are very far away I can keep people at bay by popping out and 3-shotting with Gheleon's Demise. You win vs. Arc Blade and Radiance (I think...haven't fought any radiant sunsingers with this to my memory, but I'm extrapolating since I've beaten several arc bladers in my bubble) but the other supers are problems. I guess that's how it should be since you yourself are a very big problem.