Sonrider - I have that same rifle in all black… love it.
I am just finishing up a build on a DoubleStar lower. Very high quality as far as I can tell. Better than a Bushmaster or DPMS honestly pretty close to the M&P lowers I have.
I bought three of their lowers on Halloween last year. Paid $125 each at a local shop. The finish appears to be top notch, and when I get my bushmaster LPKs in and assembled I’ll post about the fit quality.
check out the other doublestar thread on the front page: https://www.m4carbine.net/showthread.php?t=222
I am glad most have had good luck with them. I bought one late fall and wondered afterwards if I got a junker. At the time I gave $99, if remember correctly. Hopefully someday I’ll get the parts to put it together. It will be my first build and I’m looking forward to it.
bought mine after the election $129.99 from a local dealer. no issues. Putting an M4 Delton kit on it. Will buy another in the future. used a DPMS LPK with no problems and proper fit. 
Red
I myself got a DS lower very nice fit and finish .I have got mostly COLT parts going on it (,“N” Marked 4 pos M4 1st gen stock, Barrel Colt 14.5 1/7 M4 ,carry handle,side sling adapter )and a (cerro?)SP? "keyhole "upper and a BCM BCG to run it.I think I will have a GTG weapon.and I real like the roll marks I thought it was a bat first time I saw LOL:D
I did have a DS 1/7 chrome lined M4 profile barrel that was very nice but after reading Robs chart I sold it because it did not have a “F” marked FSB and would not work with My flat top with out the Bushmaster Tall front sight post.So I sold it and bought a new COLT Barrel,But if I was going to build a A2 I am sure I would give their barrels a chance
I purchased a Double Star carbine model six-months ago and it is a quality firearm. The company has been around for quite a long time and they manufacture many of the parts used in the firearm. The April 2009 edition of “Special Weapons for Military and Police” features a “hand-on” test of the “Patrol” model. I purchased mine during the height of the frenzy…being the last AR available in my town. But I purchased it for under $850, which was better than anything available at the time. I have since customized the weapon to my liking and did change the upper to a Bushmaster V-Match flat top since mine had a fixed carry handle. Nothing bad about the original upper, just my personal taste and will probably use the fixed handled upper for another build. You can’t go wrong with a Double Star.