AR help needed

Maybe, maybe not. Not trying to search for ar thread on OB

Personally, I'd just assume have two complete rifles. But, swing as I have 4 now and have 4 other lowers I may be a bit biased.

AR parts are so cheap now you could easily build one for $150-200 without a really good trigger.

If you're working with a limited budget I'd take the money you were going to spend on the second lower and invest in a Geissele trigger, better furniture and better quality barrels instead of getting 2 basic lowers and budget uppers. You're definitely going to want the better trigger when doing Grendel stuff. Personally I prefer to have each lower wearing an upper and eventually you're going to want each setup a little different to suit each of their purposes. But you got at least 2 years to figure that out before prices go back up.