Just ordered a couple of these, and am interested in what your experience is with them.  These are the a1 uppers that come in three different grades.  

i have only heard good things.

it was mentioned a little in this thread:
http://www.ar15.com/forums/topic.html?b=3&f=12&t=203788


you done gud.

Maybe I missed the earlier thread, but I attempted to contact Buffer Technologies via email concerning their A1 Colt Uppers since the ad appeared in Shotgun News a month ago.  Call me crazy but I can't spend my hard earned money with a company who can't respond to even a single email, let alone the five or six I've sent in the past four weeks.  I gave up trying to buy one from Buffer Tech and decided to build my own!