Sorry for the late response, I was relying on the fact that I will receive some kind of notification when someone replies on my post, but that turned out to be an ungrounded assumption.
Anyway, to answer your question, I had several night rides up to this date, and I can say I am very satisfied how it worked out; the mount itself seems as a reliable piece of equipment, subsequently added nuts and bolts tightly sit in place as from the day one, and the grip between the mount and the flashlight is strong.
In short, there's nothing I can complain on. However, there is something I did not think about - the shaking of the light beam when riding on bumpy road. This effect is probably hardly avoidable, but my guess is that, in this particular case, it may be a bit emphasized due to usage of over-sized and over-weighted flashlight.
PS:
I order to get some more tightening motion, I think the nut from point 3 of my previous post, can be shortened to 9 mm instead of 10 mm. As I mentioned earlier, the grip is strong enough and this is by no means necessary.
And another thing, if you want to make sure that under no circumstances you drop your beloved flashlight during the ride, you can use the supplied lanyard strap to secure it to your handle bar (like I did, for the first couple of rides).