My vote is to get familiar with the maintenance tear downs, do those thoroughly, and shoot it. Shoot the crap out of it. Figure out what your wear and tear parts are, and perhaps upgrade those, which are usually just springs.
I was at a similar point about a year ago, wherein I was about to build an AR: had found a great deal on a beautiful barrel, JP LPK, found a great stripped lower....and I was avoiding the purchase of a Colt.
I was avoiding a Colt purchase as result of Army experiences back in the 80s-either our Unit Armorer sucked or they just were not where they are today, production quality wise.
The LE agency I had trained with used DPMSs and that annoying "sproing" was still there, from almost 30 years ago. Then I smelt the pending Obamapocalypse coming, and grabbed a new Colt 6920, when Buds still had decent LE Discounts. Sold/traded off the build parts I had gathered and almost half paid for the Colt.
Then, I ordered the Brownells catalog for ARs; time to go shopping for bolt ons. Before I shot the rifle!
The AR industry is vast, monstrous and beautiful-thank God. However, I can get caught up just like anybody else in the hype. I'm not going into building ARs-I just want to shoot. I bought some scope rings, mounted my old Redfield Partner on her, and watched the Vickers YouTube vid on prepping/painting the AR platform for my purposes.
Start tinkering with too many mods and perhaps end up in left field on the paper, no meat on the table, and range time which is beyond frustrating.
What do you NOT like about the rifle and what are you wanting to do with it? If you are going to venture into the business of AR works, venture into the Brownells website of parts and videos-it's pretty darn awesome.