In search of a boost pedal for use with my acoustic set up I had a look around. Trying to find a pedal that gave as clean a boost as possible I took the plunge and bought the Keeley mini. Thankfully it delivers what I wanted, a subtle volume boost when I need it. Pros: flexible in that it has a switch to increase the boost range and another to roll off some treble. Though access to those means removing the back. It has a small footprint. It feels very sturdy, time will tell. Cons: Only one so far. I have found that the Katana mini is very fussy about it's power supply. It does not like to be in a daisy chain set up and also reacts to different power supplies. Used it with Boss PSA, TC Powerplug 9 and an EHX . The latter was ok the other two produced a whine when the mini was engaged. I now power it via a Strymon R30. Overall: The power supply issue I found a bit frustrating but now sorted and the mini is delivering exactly what I wanted.