I was thinking UMC or PMC was the bottom of the barrel. I've never even seen Tula .38 SPC.Crappiest in 38 would probably be either Tula or Blazer aluminum case. That Tula lacquer really gunks up chambers, and sometimes the primers are too hard for revolvers that have had trigger jobs, and Blazer likes to crack in the chambers, and is a terrible choice for lever guns. I love 38, and it has a lot of advantages, but I'm not sure I'd trust either of those ammos in an emergency.
38LC fires in most of the same guns, and the crappiest 38LC I can think of, off the top of my head, is MagTech - and it's "acceptable" at worst.