That's a bummer to hear. My experience with them has, so far, been excellent. I ordered a set (actually 5)Sailun S637s from them. When they were mounted and balanced we quickly realized the side wall made the tires way too tall (235/85R16)for my trailer. They gave me a full refund and remounted a set of their Big O H/T Big Foot tires in LT225/75R16. A perfect fit and I got the difference in price refunded.
So far I only have about 4,000 miles on them and they still look new. I hope I neither have issues with the tires or the company as we are preparing for our trip around the US starting in August.
Let us know how they take car of you please.