I'm trying to decide on a gas block/tube for an AR build I'm collecting parts for. I'll be using an 18" barrel with a rifle length gas system with a 15" handguard over it. So, the gas block will have to be low pro. My questions come down to aluminum vs steel, what type, and what kind of gas tube? I know that the gas system is important and a good, quality gas block will be used. But, what are the advantages between steel and aluminum. Obviously, steel is heavier, but other than that, I'm kind of clueless. Is set screw/dimpled barrel better than clamp on with out dimpling? Is a pinned style better? Just from a cursory search through several manufacturers' websites, I've noticed that gas tubes are all in the $10-20 range. From what I've read in other semi-related threads, all gas tubes are NOT created equal. Then why is there not much difference in price? Is there a huge difference between melonited vs stainless? This rifle will be a range toy and, possibly, an way to get into shooting sports. I'm not building a race gun or anything like that. If I try some shooting sports and decide to pursue them wholeheartedly, then I'll get something designed for that at a later date. This rifle is my first foray into the platform. Not a crap gun, but not a $3000 build either. Thanks for any help. It's very much appreciated!