I will be going with Torklift Tie downs from here on out,
In defense to happi jac here is their email response when I contacted them. They also said the most extreme situation they encountered was a truck and camper getting sucked up and tossed by a tornado and the truck and camper were still attached. If anyone wants the engineer report PM me and I can email it to you.
"My name is Gary Scothern. I am the Warranty & Technical Support Manager for Happijac (LCI). I have been with Happijac for 27 years and have been directly involved in the development of the Happijac tie down system. I am writing to you to refute some very erroneous information you’ve received from the folks at Northwood Mfg. It is obvious from the pictures you supplied that the failure rests solely with the anchor point on the camper. In the photos you can see the turnbuckle still clearly attached.
We have been manufacturing and selling the Happijac tie down and turnbuckle systems since the mid 1970’s and they have been used at one point or another by about every camper manufacturer that has ever come and gone over that time. I would challenge anyone to find another such failure involving Happijac tie downs. Lance, one of the largest and most enduring camper manufacturer has always endorsed Happijac as being the best and safest tie down system.
I have attached an engineering report explaining the premises upon which the Happijac system was developed, and the advantages of the system.
If you have any questions or would like to discuss this further I would certainly welcome a call."