Just a first impressions review for now, since I just got this delivered today.
I love the Plum Crazy lower! I mounted it to my other AR a couple weeks ago for some firing. It has a great single-stage trigger and fits very tightly on all 3 of my various uppers. At first it didn't seem too much lighter than my other lowers, but the more I handle it I am inclined to change that opinion. Not sure of actual weight of the thing.
Midway had a deal on the DMPS Sportical upper with light contour bbl that I couldn't pass up. Just got it today and fitted it to the PC lower. This AR is for my little wife, so the combination works great being really light weight. Again, no scales, but it is noticeably lighter fully assembled than my 10.5" SBR.
The sportical upper came complete with a BCG and charge handle, but no sights. I had a cheap little reflex dot sight I put on it for now. It doesn't have a forward assist or dust cover, so I guess she can't take it into combat in the sand. I am interested to see how it spits the brass out without a deflector.
Plans are to get it just how she likes it with optics/accessories, and then it's getting duracoated pink camo.
Will report back after I have shot it to see how the DPMS upper handles.