7.1a is secure enough, it was been up for almost 3 years until this shutdown and there are 3 officially failed code audits during this period of time.
There are a lot of the US court cases where they still weren't able to go further due to lack of evidence because of the TrueCrypt encryption.
Thanks. I found this article via reddit:
https://madiba.encs.concordia.ca/~x_decarn/truecrypt-binaries-analysis/ which seems to say the same thing you are. It's a bit technical for my level though.