Let's not get off track here by ignoring the initial post.
To me, those initial video links set a new low, and are so obviously biased with pseudo-specifications that really put me off and raise the red-flags. And I actually own a well-built Chameleon hybrid / unun or two, (both mini and normal) BUT understand the compromise. They are not my only antennas to be sure!
Like prcguy points out, both of those competing systems are based around what is essentially a random-wire with a transformer / bal / unun. In Chameleon's case, that "hybrid" is actually a specially wound unun that differs a bit from the more common toroidal type.
I opened mine up, and it is the very same technique used by the Comet antenna. G8JNJ covers the pros and cons of this balun/unun type well:
http://www.g8jnj.net/cometcha250b.htm
In the case of a non-resonant wire (or whip if you will), it REQUIRES a decent ground for any sort of efficiency. And, the lower you go in frequency with the balun of the Chameleon / Comet type of arrangement, the losses in the balun itself add up. At 80m or so, that "half winding" is what provides a low dip, but at what cost especially when attached to a short whip? In this case it is far better to utilize a feedpoint tuner.
A new user would do well to *strip away the marketing hype*, and read up on what it takes to make a non-resonant random wire work well as that is what these systems are. Are you just using the common mode of a single feedline as your ground?
One thing not conveniently mentioned is that balun / unun's don't maintain their specifications when the reactance is high! That is, they may test well with a resistive element, but when high reactance is present, that balun specification might go right through the window. Hence the need for high quality units like Balun Designs LLC and others which recognize this fact.
Yes, anything can work. Ironically, the best thing for a new user to do is build a canonical simple amateur antenna FIRST, and then if you use a non-resonant system like these later, you'll either understand what it takes to make it work well, or be a better judge of how much loss you can stand for your own working environment.
Personally, I run non-resonant systems by choice, but in order to get any efficiency out of it, you have to put in some work especially in your ground system, and do some calculating on transmission line / balun / tuner loss to see if it goes beyond the norm. And toss in radiation angles too! Unfortunately, this can all just be too much for the newcomer, especially when every forum thread goes on a tangent.
