Cant comment on mega lowers. I Haven’t even held one, just seen pics of them. Most all lowers are about the same. As long as the pin holes are good, everything else is a wash. I really dont care what written on the side of a lower.

Rock River stuff is great. Uppers and lowers. I would get a complete gun if I was shopping around for an off the shelf gun.

For a first gun, I would get a 20 inch gun with a removable carry handle. They tend to have less issues with running, they kick less than a 16 and are easier to shoot accurately. And a fixed buttstock is one less thing to break. They just dont look as cool as the 16s.

Ti plated stuff is a complete waste of time. Just pimp looking stuff actually.