You have an expensive trailer, and expensive truck, and a family on those tires.
If you have any doubt (and with Chinese tires, you should) think about the hassle of any one of them blowing, then think about the peace of mind a new set of tires will bring. Then, make up your mind.
My son had bad luck with Chinese brands only one time -- never will I put a set on anything I own. They just come apart with no warning - that's all it takes for me to reject it - the savings isn't enough either, to endanger myself or my family.