Ya I prefer a full 16" barrel myself. I chrono'd 2 14.5" Colt barrels against 2 16" Colt barrels and found almost a 100 fps difference plus I've drilled out enough pins to know I don't like em.
The Melanite is supposed to be better but I don't know. For a hunting gun I wouldn't mind an accuracy edge over chrome. But I built the same gun only with a Colt pencil barrel and have no issues making things dead.
The tube/rail I used is a Troy Alpha rail, 13". They work with a standard barrel nut.