Until the audit finds a viable reason otherwise, no critical vulnerabilities have yet been discovered, I intend to keep using Truecrypt. In fact, still installing it on new PCs I've acquired. Apparently, even Amazon AWS services is still using it.
There is no real open source equivalent to Truecrypt in terms of functionality. I have used
Diskcryptor in the past. But the same question of an independent audit could also be directed toward it?
Otherwise, you're dealing with closed source paid encryption apps such as Bitlocker. So have no idea of their ultimate security, including if any backdoors have been engineered into them?