Corsair contradiction

I love the corsair models, i even took them the the uk open at Birmingham where at least in 10th they where usable, but in 11th they’re just completely useless. And with the fact they rarely get invul saves so cover not effecting saving throws, they’re painfully fragile.whilst they used to be somewhat capable of surviving large quantities of 1w shots as they could potentially be saving on a 3/4 against 0/1ap weapons now they’re on 4/5s so weight of dice justruins them.