From personal experience, be careful with overseas customer service.
Probably the most known US company assembling RV tanks built mine. Both of them were leaking - not at a single rivet but about a dozen on each side - ruining an expensive paint job.
I contacted the company and got as a reply that I should have done the pressure test and that it was my mistake.
I dumbly assumed they would test them before shipping overseas... I was wrong.
By opening the plates at the tank root to start the repair I noticed the poor quality of the build, no deburring, rivets mostly undersqueezed.
A hangar mate had a similar experience with the same company.
Probably not all of them are like this but be careful...