Hi Blindseer03,
Transports usually are the safest place for soldiers to be. Even if they blow up, the damage dealt to the people is fairly low, unless your men inside are say guardsmen. Most toughness 4 units with good save units, like Necrons or marines would be unlucky to even lose a single model.
I cant comment specifically on the Necrons, I haven't read the new book, but their transport appears to have incredibly high armour, due to the force field [this is taken from WD, I am sure someone on here can confirm if this is true]
I say this as someone who is a definite fan of transports though. The Necron one is open topped, so all the Necrons should be able to fire out of it, while taking no damage back in return. Sounds a good thing to me.