I'm currently playing a Gibson Explorer through a spider III 150(spider haters, I don't want to hear it). It has emg's in it and I'm planning on switching them out, I don't particularly care for EMG's I'm wondering which would be a better pup. I've never played the Blackouts but everything I've seen sounds great, I've used the Mustaine pickups too but I'm just looking for some opinions on which pup is better for hardrock/metal.

I'd vote blackouts, I plan on putting them in my ibanez. I've heard a mixed bag about the livewires.
I would say to check out some passive pick ups, those active pups are better for tube amps.