You should ask this at
www.fnfal.com I've never shot one (Century), but have heard all kinds of things, and it's always hard to know what to believe. It's an entry level rifle price-wise, so it's unreasonable to expect an excellent rifle. However, there's no reason it can't be a good and reliable shooter. If it's not, you get to tinker with it to make it better, and that's half the fun.
One thing I would do is to check the headspace on the rifle to make sure it's safe to shoot. Because the FAL has an adjustable gas system, you should be able to get the action to function reliably. If it does not, some tinkering and parts replacment should fix that.
I would tend to disregard the pronouncements of the hardcore purists. They will immediately say "it's a piece of shit" and half of them have probably never even held a Century FAL.
The FAL is a wonderful design, and in some ways superior to the AR. They're a lot of fun to shoot. Go try it out and see.
I own 2 ARs, 3 FALs, and am currently building a 4th FAL. Love em all.