I honestly think nobody should deal with Myrig for now until they sort these delays and slow response issues (read OP), however, it's normal for the address to be like that, UPS offers "Store mailbox services", which is just another way of saying a PO Box with a full address, so it looks like Myrig are trying to hide their workshop address for some reason, that alone isn't something that will raise a big flag for me, but the other reasons mentioned above are pretty serious.