I know nothing about Hemlock, and very little about Meshuggah. I think I might have Chaosphere, but I'll be danged if I remember anything about it, but "math metal" sounds vaguely right. I think that was right around the time where I just discovered that all metal bands had drifted towards cookie monster vocals, and I was getting extremely turned off by that, so may not have given them much of a chance.
Ministry fucking rocked live, the last time I saw them, which was the tour that produced the live album, In Case You Didn't Feel Like Showing Up (Live). They started with that sample loop that opens...uh..."Breathe"? Or "Thieves"? I forget which one. And then when they started rocking, the entire crowd started jumping up and down ("doing the pogo"), and I was literally lifted off my feet. I had no choice but to mosh along.
Good times.