Well, I went and did it. I swapped out both uppers on my 6.8 AR's and installed the completely slick sided uppers from Palmetto State Armory. Now I haven't had a chance to take it to the range yet, but so far it "feels" lighter and handier and definitely sleeker. I am a right handed shooter, but my wife and daughters are lefties, not that they shoot alot, but getting brass to the face or neck was a concern, we will see during range time.
I am a subscriber to the K.I.S.S. theory, so it was a relief to get rid of those "useless" appendages hanging off the right side of the receiver. I didn't want to take the front sight off, so I have an open ended barrel nut wrench, but upon trying to remove the gas tube first on the RRA AR, it became unusably damaged, so another is on the way.
Now, I have to figure out what to do with the old uppers.
Here's a few pics:

Kinda cool. I like it.

Nice!

I like that alot. Been thinking about building one. Thanks for the pics. They might have just made my mind up for me.

All my ARs are slick side. I don't care for the forward assist or shell deflector. I think the thick walled DPMS Low Pro receivers are stiffer than MilSpec receivers which should help accuracy.

The new gas tube had been delivered by the time I got home from work, so I put it on and headed to the range with both rifles.
The buis and red dots had to be re-zeroed, but not by much and they both functioned flawlessly.
The empties do get flung at a sharper angle to the rear but not at a extreme rate, they landed at about 1.5 to 2 feet to my right rear at about the 4 to 5 o'clock direction but I had a net they were bouncing off of which didn't give me a truly accurate result of where the empties would go.
I did fire one left handed just to see how a lefty would fare and one bounced off of my right forearm just forward of my elbow leaving a nice little round red mark and the second one hit the right collar of my shirt and fell away.
I could see it being a problem for left handed shooters.
But all-in-all I'm pleased with the conversion.

Bout' time. Enjoy!

My SPR'ish build is a billet slick side upper with port door.  I like the look of slick sides a lot!  I do not have a brass deflector, but you can see the brass hits the receiver as it it did have a deflector.  The billet is a bit thicker than a forged receiver in that area.  I'm a left hand shooter and no issues at all...