It all comes down to how much you're willing to spend, and most guitarists don't have $3500+ sitting around for an amp head.....BUT....yes....the Herbert is the most crushing killing machine I've ever heard on a 4-12 cab.
If a Bogner XTC is the ultimate channel switching Marshall, then the Herbert is the ultimate Triple Recto.
I tried out a Herbert for about an hour one day, using a LP, Strat, and Charvel EVH. The monsterous gain that comes out of it is almost scary. Massive headroom on all channels, and the amp is built like a spaceship. It's not really vintage or organic sounding like a Bogner. It's modern, tight, and just screams metal. The clean channel is nice and glassy, the midgain is pretty versatile and can be used as your heavy channel as well. The hottest channel is pure mayhem. It could disembowel an animal at 100 meters. LOL
The Triple Rec is no slouch either, and much more reasonably priced. If I had the money, and wanted that sound, I'd figure out a way to get the Herbert, but the price is just obscene. It all depends on what your income level is.
For metal, Diezel is the end of the road.