I had purchased a Spikes complete upper from aim surplus. I was having issues with it feeding ammo. I diagnosed the problem to be a gas leak at the gas block. Called spikes, they sent me a call tag and I sent it back. I received it back in 2 weeks and not only did I get the upper back, I also received a brand new BCG and charging handle! That's customer service baby!

Glad to hear the good serice from them. I recently got a 14.5" mid-length upper from a member here (who got his from Aim). Thankfully no problems so far.