I put together one of the lowers I bought in the original group buy last night. Had an issue with the safety selector, it seemed to get hung up and wasnt a positive movement. Any way it was a CMMG lpk, I emailed them last night around eleven. Got a response this morning around ten asking form my address so they can make it right. Sent them my address and 10 mins later got an email saying the selector detent and spring will be sent out today. Apparently they had a bad batch of selector detents. Overall I was pleased in the quickness in which they responded. Nice that a company is standing behind their product. Just thought I would share.