This is the second time I've purchased this valve. I find it great for first stage, specially for "british" amps (orange in my case) but also marshall, vox... not as full or deep as RT010, but with a more complex mid response due to it's tighter low end. Haven't tried it as second stage (normally eq), but I assume it should be great as well. Basically, campared to RT010, tighter low end, great for rock, blues... if it's metal you're after perhaps the other one woud do the trick better for you