I decided to go with Tri-Flow.
History on the reason for this forum post:
I have two RAM trucks both with B&W Stow and Go Hitches. Both had standard hitch locks (usually ~$15 to ~$25). One of the hitches was stolen.
I decided to buy very expensive hitch locks for both trucks thinking that they may be more theft resistant. I could not get the old lock off of the truck that still had its B&W Stow and Go Hitch. So I had someone bring over a ~1.5 to 2 foot long 2 inch SCH 80 pipe. It was so easy to snap off the old lock. I guess if someone used a little bigger pipe they could break off the new very expensive locks.
I just lubed up the two new very expensive locks with Tri-Flow. I will have to remember to lube them about every 6 months.
I know: Locks are made to keep honest people honest, not to keep criminals out.
If you are interested this is the very expensive lock that I purchased and installed on both trucks. Note: This is not where I purchased them but this reseller has better pictures.