The question to ask is why would you even take a risk trusting that shit. Truecrypt is free and open source. Use Truecrypt. A more precise answer is that you really cannot trust proprietary encryption software, and there is no reason for you to. I mean, maybe it is not backdoored, maybe they implemented it correctly, but who knows? Not me, not you, only a few people at Symantec know if it is backdoored or not and not even they know for certain if they implemented it properly, because even with open source software that has no known defects nobody knows if it is implemented properly 99.99% of the time, but because it is open source arbitrary people can try to ascertain if it is correctly implemented.