Definitely tempted by the A2 upper:
https://www.brownells.com/new-brn-retro-uppers/?sort=NumberOfReviews
I started a thread on this a few days ago, but no one wanted to discuss these things.
I guess “retro” is for the older, “retro” crowd 
It’s depressing that the A4 is retro now.
Yeah, that must make the A1 prehistoric.
I have a A2 dilemma, years ago I built up a upper with a FN receiver, only one I had without M4 cuts, and a Colt barrel, then couple of years later I traded for a like new A2 with Colt receiver and FN barrel. Every time I think about it I get the urge to strip em down and swap parts but it really makes no sense because they are both good shooters. Woe is me!!!
I am excited that the A1 birdcage is available. I did have to put in a notification request, but I do want a few of those.
I’d suggest these. > https://ar15sport.com/product/a1-bird-cage-flash-hider-arpart-70/
I believe the ones Brownells is selling are possibly made by Innovative Industries and those have a black oxide finish instead of phosphate like the ones from AR15Sport.
The ones from AR15Sport are made by L.W. Schneider in IL.
I’ll gladly add this; BROWNELLS needs to offer the retro COLT GRAY again like they did a few years ago, along with chrome-lined barrels. That’s my preference anyway.
Awesome. Thanks!
Bushmaster is selling out of their older grey A2 stocks, I just ordered one. Will do a side by side with a Colt A2 that I just swapped out. The new Colt AR15A4 rifles do not have the yeee old greyish stock color of yore… Hoping the BM does and is of sufficient quality.
https://www.bushmaster.com/shop/snake-pit/a2-stock-assembly-kit-discontinued/
I don’t remember ever trying an A2 stock that I thought was lacking… unlike most of the A1 aftermarket options.
No problem. I like them enough that I have them on almost every rifle I have. 
Was not aware that the newer Colt A4 stocks were not in grey anymore. Last ones I got from Brownells a couple years ago were.
But anyways, that grey/silver color is actually a finish or dry film lube of some sort. It’s not actually the color of the polymer that the stock body is made of. I ordered a couple A2 stocks from Fulton that were uncoated and as black as Zytel normally looks. The Fulton A2 stocks were obviously made by the same place that was making the Colt stocks I got around the same time based on the marks left by the molds. The only difference is that the Colt stocks were grey/silver finished.
I noticed that the grey/silver look was a finish on the Colt stocks when the toothbrush I was using to clean them along with warm soapy water was darkening from scrubbing the stock down.
Just now ordered 1 myself to see what I get compared to what I have already on hand.
Where do you normally get them?
The current/modern A2 stocks suck in that the off white yellow foam fill they use is much softer than the hard darker yellow foam fill of the older A2 stocks.
Something about the old hard foam being regulated out of use by the EPA according to Mike of NoDak Spud (H&R/PSA).
Brownells and another place I don’t recall. Might have been JSE Surplus, not sure, they seem to be the same.
I never got one from JSE. All I know is that the A1 bird cage flash hiders on the Brownells site look very similar to the ones on the Innovative Industries site that are finished in Black Oxide.