I have a group of H. Pantostictus "Tambaque Gold" which is supposedly a new variant of Panto. I can say for sure that this fish has more gold in it than regular pantos I've kept. Cool fish. Herichthys rule!
That was my experience as well. Here are some pics of a breeding pair I had earlier last year. Very susceptible to stress bloat and very violent toward each other. These were described by Conkel as Herichthys pantostictus (Blue labridens) Rio Panuco: