Why people want to "buy in" to small miracle antennas is somewhat of a mystery to me. TANSTAAFL* I guess they "want to believe" Yes the CHA250B the Tak-Tenna, the Isotron, the Maxcon, the list goes on and on. Do they "work", sure, but as compared to what? Compared to dummy loads and light bulbs, they work. But everything "works", it is all a matter of degree. Do any of them work as well as a dipole or 1/4 wave vertical with a good radial field? Sadly no. But they make some people happy. They wouldn't make me happy. Just reading about the Isotron on their website about makes me want to throw up. They mention that the isotron with its flat aluminum plates has as much surface area to interact with the "atmosphere" as any full size wire antenna. Wow. That's a good one.
*There Ain't No Such Thing As A Free Lunch