Well gents, tried it in anger for the first time last night.
Firstly the good things....
Headroom - tonnes of it. I've had some amps before that compress/limit the signal when playing aggressively. My old Markbass SA450 used to do this but maybe I was just asking too much of it. The Shuttlemax is different, had the amp volume set at 8 'o' clock (almost off altogether) and it's blisteringly loud, ended up controlling the volume on the preamp section! Ha. Insane. Tone shaping possibilities are endless, 5 way footswitch lets you choose between Tube/Fet, a mix of the two on/off, Low boost, mid scoop, high boost. The amount of each one is set on the amp, so you can for example choose exactly how much bass boost you want then switch it in/out at your leisure. Marvelous !
Bad things....
Power switch is on the back... which is annoying when it's rackmounted.
Thought the mute might have been included on the footswitch, which it isn't.
The blue LEDs on the amp are stupidly bright to the extent where you struggle seeing what's actually written on the face of the amp...absolutely blinding.
All in all though... one very happy bunny !!