I have 3 Century "cobbeled up" semi-auto battle rifles!
And really all have or seem to be perfectly servicable, decently made blasters.
I've had a Century L1A1 for a long time, no issues whatsoever with it.
I bought a WASR-10 hicap late last year. Only real issue's here were the off-center and crooked rear sight notch. The sights and fittings all being fairly squarely mounted. So new they didn't even varnish the stock, and crude, but reliable, accurate and fun too.
Then last week I bought myself a Century C-15 Sporter. An interesting rifle, essentially a military surplus Colt M16 A2 thats been refurbed into a AR-15 Hbar sporter rifle. Most or all of the upper is Colt. New lower receiver with what appears to be a mix of used and new trigger/lower parts. Some parts are refinished, some are old finish, some look new. From what I've shot the thing in the week I've had it, works like a champion! Eats .223/5.56 mm ammo like it's going out of style, and seems quite accurate.
I've heard the horror storys about Century's quality. I believe them too! These people have turned out some seriously shoddy stuff. Yes, probably best not to buy a Century semi-auto sight unseen.
All that said, I've had nothing but excellent success with my three Century battle rifles. No jams, broken parts, manufacture issues(excepting the WASR-10's bogus rear sight notch!), perfect accuracy fit and function!