I think people are referring to Bi weave Vs Class A shields, not like for like class C. Bi Weave only come in class C, so Here Is what I do and I think people are referring too :
I use a 7c Bi Weave, this draws less power than 7a normal, allowing me to have an extra shield booster A0 (and still using less power than 7a), this means my over all shield capacity is about 10% down on having the 7a...BUT.....It recharges 50% quicker than the 7a, So if I loose the shield totally or it is very low I can leave the battle for far less time before it is back at full charge, and for a 10% loss it is worth it for that gain imo.
This depends on your choice of ship and amount of bays available for upgrades I guess.