I play simple straightforward, slightly psychedelic rock (influenced by velvet underground/spacemen 3/rolling stones), and the Twin Tube is perfect. I've been playing for 15 years. I used to use an SG special until upgrading to a ES-335. It sounds fantastic, and as I upgraded my guitar and pickups, my overall tone (and indeed that which was effected by the pedal) really improved.
I would probably replace this pedal, but before doing so would try to find a boost pedal that competes with this. If I could do that as well as find a more personally ideal fuzz pedal, then I might go that route, but I love the way this thing sounds, so I would probably get another one.
Cranking this pedal through a cranked up tube amp is something to behold.