But while the shield only mitigates 25% of damage, that's only an extra 5.3% to what you would have normally. I feel like the Alacrity from the Combat Medic gear also hinders your performance a bit.
Maybe I'm wrong, and that's a high possibility, but I'm just skeptical as to how all of this is worth giving up a 15% Rail Shot Crit / better (DPS) stats on gear.
Also, are you taking the Supercommando 2 piece for the extra Guard sustain? It doesn't seem like that helps the shield, but it makes sense in PvP as that's a pretty integral aspect of medal attaining.
EDIT: My bad, The PvE Supercommando gear. Gotcha, my bad.