I do not usually enter into much conversation in these forums, but this one I could not resist. I have been down this road before and I am going to tell you my findings. I am left-handed, I am a LE Range Instructor and I used to shoot quite a bit until the ammunition cost prohibited it. My past experience is not up to MANY individuals on this website and more than some.
I have been shooting righthanded AR's for 20 years prior to Stag Arms coming out with their new gun. I wanted more than they originally offered, so I purchased the upper and bolt assembly and shipped it to Bushmaster to have them build it (I have owned a gunshop since 1989, but have never taken the time to build my own gun...go figure). I was able to have their 2-stage trigger, and every other bell and whistle possible installed and then it came home to me.
I was COMPLETELY pleased with the firearm and the work done by Bushmaster. I found some of the bells/whistles to be nice. Specifically the Bushmaster 2-stage safety, ambi-safety and the nargon magazine release. The gun functioned flawlessly and it grouped very well.
Now for what I didn't like and it is very simple. I didn't like not having the ejection port on my dominate side. I learned it was much quicker to view a failure to feed with the ejection port in front of me without rolling the gun. I would also like to say, being left-handed and left-eye dominate in a right-handed world is not fun in general, but we are getting the best of the bargain with the AR. If you start working malfunction drills, you will see what I mean. Malfunction drills need to be muscle memory and you shouldn't have to look every time, but when you do need to look...it is nice to see so quickly with VERY limited movement.
Maybe you will find the Lefthanded version to be exactly what you want. I am merely giving you my findings. What works for one, may not work for another.
With that said, I just ordered a new Wilson UT15 and sent it back. The upper to lower fit was as bad as one of my well used Colts. Sent it back without shooting it. I was VERY displeased it was shipped with an ACCU-Wedge new from the factory. In my opinion, $2,000.00 + guns should not be shipped with an accu-wedge to make up for a loose fit. Not that it won't function, just that it was disappointing.
I am considering a new LMT, Bushmaster Custom Shop PRS or a Knight's Armament SR-15 IWS E3. I have had all the standard issue stuff and want to see what all the hype is on the "Top Shelf" guns (if there is any remains to be seen). Might regret it when it is over, but as my Daddy always said, "We shall see what we shall see." I hope I am extra happy with whatever I purchase, as I am just like everyone else...trying to figure out how to buy the next ball glove for the kid and not make them eat mac and cheese EVERY single night! LOL!