Inspiration hit and availability of 18" barrels was low, so I changed direction. Blem PSA lower, blem BCM upper, Roscoe 16" mid-length barrel with F-marked front sight gas block installed by DS Arms, DS Arms BCG, Delta Ring Kit, A2 flash hider, front sight spring and detent (had a post leftover), PSA B5 Systems EPT lower build kit in FDE, and FDE B5 Systems forearm. Notice I forgot the crush washer, so that was a PSA pickup from one of their stores.
I wanted to try a Roscoe barrel, and wanted an M4 style when done, so the one from DS Arms was perfect. I prefer mid-length systems if I'm going with a 16" barrel. B5 seems a little less well known than Magpul, so I thought I'd give that a try too. I really like the forearm. It has a slimmer, easier to grip profile than my A4 clone. It didn't hurt that PSA had the B5 lower kits on sale when I bought mine last year. As it sits, it does wear Magpul MBUS rear sights, which I've always liked. Eventually I'll get a magnified optic of some variety, but I'm fine with the MBUS for now.