I'm with you jBernard.
As a business owner I know that responding to every potential complaint can be tedious and time consuming.
I'm certain that this thread has been on his mind but think about it this way.
What can he say that will prove or disprove the concerns raised here?
Have you ever heard of any of his frame conversions failing?
I haven't, but like many others I chose to try it myself because I was too cheap to pay for a first class job and I wanted to see if someone as inept as me could do it.
Remember he does not make the basic material.
All he does is cut it and bend it.
It is up to you to know what you are doing and do your own engineering (Not WAG engineering).
If you run a stress analysis on the material you will see that it is more then enough material to handle the load providing that the load is correctly divided on it's mounting points and providing the head stay is properly engineered.
From the pics I saw there are problems with that design.
I'm not sure that comparing this situation to that of Stewart is really relevant.
I'd like Stewart to sign up under a different name so he can provide his technical expertise but, I would not buy from him
I will be doing another conversion after I get my current one done and I will buy another set from Jfab