I recently ordered a transmission kit for my 70 Cuda (sorry, I do own a Charger too). The kit arrived in England with the transmission box looking like it had been thrown from the aeroplane rather than landed in it. Upon inspection the tail shaft of the trans had been damaged. I told SST and without fuss they have quickly sent me a replacement (via a different courier). Great customer service.
I also had good luck with them. They repaired something from another vendor that had problems.