I've built quite a few machines for others as well, and almost always use AMD. One guy said it was the fastest computer he'd ever owned. It was back in the day about 5 years ago, he had a little core 2 duo and some old radeon card in a dell. Upgraded him to a 1090t, 4gb of ram, gtx 570. His big game was battlefield bad company 2. He loved it. I'm guessing that old system, you could toss another 8gb kit in there, pop in an r9 380x or try even a 390, better cooler and overclock that chip. You'd be good another couple of years I think.
But of the systems I've built, the only one that ever had a question was someone who was playing an older unoptimized mmo, can't remember the name of it now. But I did introduce him to Crysis by showing him the demo. I built him a box with an FX 8350 and gtx 770. Of course, that build owned the demo, so I think he may have been going to get a copy lol. But I really don't remember hardly anyone ever complaning. Most people can't believe how much faster it was than their old systems.
What's nice is ever so often people give me old systems that are broken. Got one that was an hp, bad board, but had 8gb ddr3 memory, 1TB hard drive, AMD phenom ii x4 820 I think, dvd burner etc. Lady bought a new computer instead of messing with that one. Just wanted the data from it. Either way, it was nice, I got a new board on a combo deal and a case. Working on setting that up as an office system for my wife. She does vinyl designs etc from home during the evening, and her laptop just doesn't handle it well. So either way this will make a nice upgrade for the little that I have into it.