I have mine connected,via finks loom,so it only works with Ign on .I have no experience of the Sparkbright unit, but they appear to be much the same thing (maybe even the same LED but with different electronics?) and the same price. The Gammatronix motorcycle unit indicates fewer conditions (so less chance of confusion I guess?) but it also switches to a lower power mode to indicate battery levels when the ignition is switched off, rather than needing to cover it to avoid significant battery discharge over time, unlike the Sparkbright, according to their website at least.
I think either will do the job admirably. If I was storing the bike for a long period (like several months plus), I think I’d be inclined to disconnect anyway.
Ask the Doctor: http://www.sparkbright.co.uk/battery-voltage-monitors.phpHi Pad
What if any is the difference,to the sparkbright one i have fitted ? . Never understood what it was telling me