Your probably right, they make crap, sell it and then never want to answer the phone because it is just a long line of people wanting their money back.
Report them to the BBB, then at least they get an official letter and have to respond to the letter or get written up by the BBB - doesn't really hurt them too bad, but after a few they get investigated and can have their license pulled. Sometimes it works well to get them to resolve the issue so they don't get written up!
2008 E93 335i, MHD, HPF IC, Injen Intake
2016 X5 M-sport 35i JB Stage 1
2013 Mercedes C63 AMG Eurocharged V6 540 HP