I play in a band where I sometimes use an AC30's built in tremolo + an additional tremolo for certain psychedelic effects. However some events just don't call for (or allow me) to bring an AC30, so I bought one of these to stick at the end of my pedal board.
This is where this is great - it's a fairly authentic replication of a sine wave 'Bias Trem'. It has the same level of depth and speed variety you'd normally have on an AC30, that is to say the speed is quite limited. Sine oscillators are like this by design, so for those who want a jack-of-all trade trem I'd look elsewhere. This is a recreation of a specific design.
It does like the variations in power amp distortion you get from an AC30, but in the FX loop of an amp it certainly could provide that. At this price point, who is complaining?