I apologize for the double point. I just discovered there is a KAC specific sub!
I'm looking to buy an SR-15 upper for my first AR. I'm really torn on deciding between an 11.5" or a 14.5" barrel. My reason for buying an SR-15 is really for the reliability. While I intend on this project not being my last, I do want a rifle that I can build a solid foundation on while being a go to rifle for training, home defense, and if society goes to shits for a bit. I live in a state that allows SBRs and since I planned on making a 11.5" way later down the road, I intended on SBR'ing my lower receiver anyways. So I'm just deciding on which barrel length I want to begin learning on and to maximize the reliability that KAC is known for.
Some considerations I had were that a 14.5" rifle would be more reliable, less concussive, and can be used at a longer range (even though there's nothing but mountains & trees here). While an 11.5" rifle seems like it would have to be suppressed otherwise the flash and the noise would be too much. Also saw something on InRangetv about how going below 14.5" does funny things to guns with DI. However, an 11.5" rifle would be considerably more maneuverable inside buildings and cars, and could be carried for much longer if I ever needed to.
Another option I had is going with a 16" upper but it seems like there would be no benefit other than not having to get an SBR stamp since from what I read, it's only a market that was created because of the NFA.
EDIT: I plan on also purchasing a KAC lower as well. Purchasing them separate since a local dealer is giving a pretty significant discount on the uppers and complete rifles seem to be out of stock everywhere. I assume that every upper will come with its own buffer tube.