For how little it costs, this amplifier is surprisingly well made. Despite being constructed primarily out of plastic, it feels really solid and high quality: the gaps between the parts are even, the on-off switch feels firm, all three dials turn smoothly, and the battery status LEDs are bright and clear. On paper, its features fit my needs just perfectly: I wanted something I could use with my headphones, so as not to disturb or be disturbed. Unfortunately, while the “clean” tone is surprisingly good, there is a clearly audible high-pitched noise that ruins everything. I tested it with two guitars and two headphone cables, and the problem persisted. I do not know whether I got a defective unit, or it is supposed to be like this. If the latter, it is unacceptable. Sure, in certain control dial configurations, that high-pitched noise got a lot quieter, but it was always there. If that noise was not there, this would be a brilliant product!