Had a bottle of this for about a year before I convinced myself to try it a few months back (had read bad reviews). Think the bottle was from the mid-late 90s, though it's hard to tell.
It was like tar in the glass - syrupy and jet black. Tasted more of soy sauce than beer tbh, harsh burnt flavours, almost salty.
I think I got about a third of the way through it and had to stop. I've seen suggestions elsewhere that it would make a good BBQ marinade, maybe not a bad call!
Anyway, I'm glad I tried it, but would not buy another.