Over the last weekend ended up completing my first AR-15 build using a 80 lower receiver which I bought from this company. Everything worked perfectly, no problems at all. Even after few times of shooting my build on the range I had no issues. I can tell that these lowers are good quality and I had lots of fun building it. I am now inspired to do a different type of a build and will use steel fox to get the parts I need to put my vision together.