I have the lights for over 2 weeks now, so feel I am ready to review them.
I have mine wrapped around the top of my balcony, luckily there was exactly, to the cm, enough to do this as dictated by the regular intervals of the railings, but that is by-the-by, the lights come on after a days charge at dusk, or if a pigeon sits on the solar panel... You can have it come on as either constant light or as flashing, note it is a flashing rather than a flickering.
Two days after I have set it up, we had some torrential rain fall causing flash floods around the area, and when I got home I was a little concerned to see that the lights were not on, I assumed that the rain had got in to the casing and shorted out the battery, however with a few seconds of shining the light from my torch on to the Panel, the lights then flickered in to life, albeit for a second, so realised that unlike some solar powered items this one needs a relatively bright day, and finds it difficult to convert power on days when its very overcast (Dark clouds only not white clouds).
I have Solar Panel facing south and on an average UK day (little sun, little rain, a little overcast) it gets enough power to charge the lights until sunrise.
Overall I am impressed and I am considering getting the white ones to mix amongst the blue ones.