I have both a Century CETME and a PTR-91.
The PTR is a better rifle in every measurable way, but I also have twice the money into it.
My CETME (and that C308) are built with surplus G3 parts and as few new parts as they can use to get it to work, which means in addition to CAI needing to have welded it up correctly, parts can be of varied age and wear. On my CETME I needed a bolt head, locking piece, and rollers to get it where I wanted. Probably could have skipped the rollers, but I had bought them first. Good news is G3 parts are cheap, so that was only like $60 or so.
So here's my thoughts after owning several CAI built rifles: CAI offers a lower entry price than just about anyone else, but they get there with worn parts and iffy assembly. If you are technically compitant, have tools, and are willing to do a little work on a "new" rifle, you can get a good deal on a neat rifle. Rarely is one so bad it's unfixable, but often they will need a little tweaking. If any of the three above don't apply to you you are better off buying a different rifle. By the time you buy tools and parts, or pay someone else to work on your gun any cost savings CAI offers will have been negated. My CETME is a great example of an early '50's battle rifle.....now. not so much when it shipped.
On RDB rifles in general, they have different ergos. They work for some folks, not for others. I like them. As a lefty the charging handle works well for me.
I think they are the most reliable of the "big 4" semi .308's. They will eat pretty much anything you can stuff in the mag. The payment for this is a brass will be a bit beat up, but it won't matter because it will be thrown so far away from you you'll never see it again. Recoil can be harsher then some other designs. (An FAL especially can be soft if you fiddle with the gas setting). I would expect somewhere around 2.5 MOA with mid-grade ammo. That rifle has CETME sights so they aren't as good as an HK, but are servicable. Optics will take a claw mount to put on, and some of those are good, some are bad, that's a post unto itself. Mags are still dirt cheap.