If you look at the battery tray in a Halcyon Scout you'll notice that the end is rolled over and sits in a little groove on the end of the body. The roll makes for a more consistent connection between the reflector and tray.
In the clones that I've seen and used (quite a bit, actually) the tray is made of a straight piece of copper. In these the tray side twists around the batteries each time it is turned on or off until it gets shortened enough that the light only contacts when the head is turned all the way in. The end of the tray on those also digs into the metal of the reflector and makes a bumpy surface there. Once this happens they will turn on and off every time they are tapped, which is really unsafe for obvious reasons.
I've seen this happen with 5 lights of the same make.
I don't know about all the different varieties of clones, and the ones I have aren't the canadian extremes, but I would not use anything without the rolled tray top. Personally, I think the Halcyons are worth the extra money.
Maybe somebody could comment on their clones?
PS I have heard that Halcyon introduced their H logo bezels because of frequent changes and variations in quality of the UK bezels.