So far so good! Overall I really pleased with this purchase. KYGUNCO was super great to work with. If you're on the fence on the Panzer I would say it's worthy for the price. Since purchasing I have added some goodies from Dave's metal work and all has worked great (extended tube, tactical bolt, speed bar, 2 round replacement tube) . For the price you can't go wrong with the Panzer M4. I highly recommend cleaning the gun first, lots of shipping gunk on it but after a good cleaning it was great. Also IF your curious and not happy with the fixed stock Panzer as well as other manufacturers have colaspable 3 position stocks. (my next upgrade) Still no where near the price of admission for the real deal M4....Some people in reviews mention having issues with bolts being loose on the rail or other places and I had none of those issues. Great purchase!