My mistake, the x0 has no mode memory. 
It has been said that the doubling of lumens only yields a 25% increase in apparent brightness to the human eyes. I decided to put this claim to the test on a large scale in my garage. After playing with my 250 watt/25,000 lumen (variable brightness via external potentiometer) LED highbay light while plugged into a kill-o-watt meter (to measure watts), I can definitely attest to the validity of this phenomenon. The sweet spot in apparent brightness vs efficiency for that light is around 75 watts. Cranking it up to max creates a whole lot more heat and eats power without a whole lot more apparent light. Sure, it’ll impress the hell out of my lux meter but not much else. From 125 to 250 watts, observable changes to my eyes yields about 20-25% increase in brightness.
To confound this even further, LED lumen efficiency plummets as power is increased and really suffers as heat increases. So when you read about mods where amps are increased from, say 3 to 5 amps, the bump is noticeable but not astounding.