Great Practice Option for Satch Tone and Soloing!
The Vox AmPlugs are fantastic - lightweight, plastic devices that take 2 AAA batteries, plug directly into your guitar and give you loads of tone and power for practicing with headphones. While the AC30 Amplug is the shining star of the line, I'm also happy with the Satriani signature model. Like the "Lead" Amplug, it has a delay option (though the delay time is fixed). It's basically like a fading echo effect, and really just adds depth to solo phrases. Since the Amplugs don't have reverb, it's a nice option to have.
The overall tone is quite good, though it varies a great deal from guitar to guitar. I played it through a Jackson DR6, and it was fantastic. My Les Paul, not as much. I think it would excel with single coils. There is a constant "hiss" sound when you turn it on, but not noticeable during playing. The distortion works best on the higher gain settings, and it's a nice thick tone, which sustains nicely. Highly recommended, though you might want to investigate some of the other Amplugs first.