it kind of reminds me of Gwiemers Holy Crap Bass
That's because it's the same bass. I've been away for a while. The ET-288M was a fair bass. When I routed the bridge into the body further, and put the Barts in, she became a beast.
In good shape, I'd say you MIGHT get $450 for one of these. $800 is just plain insane. The neck is pretty beefy, and there really wasn't any relief designed into the bass, so they weren't the easiest bass to play.