No Century, except the Century L1A1 Sporter thumbhole sold in the late '80s/early 90s, which are excellent.
The advice that only "1 in 500" Century or Entreprise (it's Entreprise not Enterprise) have a problem is rubbish. More than half the post-thumbhole Century guns I've handled won't run. Entreprise-built guns were much better, but no anywhere near DSA.
No Hesse, period.
Home builds are suspect. Despite claims in this thread, without the right tools you will not fix the two most common problems, that being (1) improperly timed barrel and (2) wrong locking shoulder = bad headspace.
Don't get me wrong, there are awesome home builds, even those having fixed Century and Hesse problems.
That said, $1200 bucks will get you into the DSA Voyager, but it could also get you into an excellent home-build. It's a matter of risk.
If you can shoot it, try it, if it works buy it. If you can't verify it works, skip it or buy a DSA.