Chaining EPtS III for 125 power means natural regen over 1K per tick on each facing. its actually the only time, when the +shield regen console is usefull.
Especially when used with tactical team, this combination can make a cruiser near indestructible. A while back, I was in a cap and hold with my escort and it took 3 of us focus firing a sovereign with the borg set to finally bring it down, and only after a long time. Very tough set, if you can set the ship up and pilot it right.
My fleet escort is the only ship I have that runs the Aegis set. I don't know why, but for some reason, the reactive shielding just doesn't work that well on cruisers. Yet with the added defense, the Aegis set is wonderful on escorts. Pretty mind boggling .