So I've finally made the first step to building my first AR-15. I've picked up a Roggio stripped lower and plan on building it with a Del-ton rifle kit. I have a couple of concerns/questions and have got a couple different answers depending on who I talk to. I have read a couple different articles about it, but I would just want to get some feedback on it for my uses. 1: Is 1/7 twist that much better than 1/9 twist. Is it worth paying an extra $65 for a chrome lined 1/7 twist than a regular 1/9 twist. 2: Relating to the 1st question, is chrome lining worth the extra $45, and why? 3: M4 feed ramps on the upper, are they worth the extra $25 for them, or is it more or less just a gimmick? From what I've heard, they are good for larger (65gr+) bullets, but for majority of people, won't do much besides reducing jamming by a very small percent. I'm going to use my AR for mainly target shooting while moving and some longer range stuff. I would like to keep the cost on the build down as I still need to venture down the road of optics after the build is done.