“Encrypting your Windows hard drives is trivially easy; choosing which program to use is annoyingly difficult… Based on what I know about BitLocker, I think it’s perfectly fine for average Windows users to rely on, which is especially convenient considering it comes with many PCs. If it ever turns out that Microsoft is willing to include a backdoor in a major feature of Windows, then we have much bigger problems than the choice of disk encryption software anyway. ”

Source: Encrypting Windows Hard Drives – Schneier on Security