If the venom gets shot down, nope they are toast. But then a 10 man squad isn't likely to survive their raider getting shot down + enemy fire either so... Survivability isn't really a dark eldar thing even at the best of times. DE really emphasis the idea that the best defense is a good offense. I suppose an all Wrack/Grot list could be counted on to weather some fire (or if you had your warriors sitting in cover maybe) but that's an entirely different type of list.