I just inspected mine than they're fine, just like they were 6 months ago, and a 1 year ago. The only time my loosened up was shortly after the install and the torque recommendations were a mere 70 in/lbs. I cranked mine up to 100 in/lbs and never had a problem since. No thread locker either.

 

A joint member of this forum and our infinitiFX.org forum started a thread on this issue awhile back. It was a good one to bring our attention to over there.
He had discovered this thread while here and shared the knowledge with the rest of us.

Here's my post from over there.
This is just last week.
I'll add it to the rest, here, just to document it.

Just had mine checked this AM while in for a new oil filter.

All 6 inside bolts were loose.
A couple, quite loose.
None of the outside bolts were loose