Ok, joystick now back with me , went out for a pootle last night and can report as follows.
It fares well in the ‘shine on the shed in the garden’ test, incomparably brighter than before and closer to the Diablo mk3 I have.
I used it on the trails as a helmet light in conjunction with my Lupine Betty on the bars. Its a revelation, lovely focussed beam, no dark patches in the light, just a great spot light.
However, in order to test it I ran it full power and after 40 minutes it started to periodically flash, it still ran on high power but every ten seconds or so it flashed. At this point I put on the Diablo so don’t know how long it would have gone on for, will do further tests.
In practice I would use the medium setting for non-downhill sections, I will see how that affects burn time. Haven’t tried piggy back on it yet, again will try in due course.
Of course the Diablo only lasts an hour on full chat too, battery management is always going to be part of a powerful light with small battery, and I am confident that a combination on medium and full would get it to go well beyond an hour..
Will update next time used.