What specific bands do you want to listen to? There are some antennas that perform much better than others in cetain frequencies ranges because they are tuned for that range... but also, there are some antennas that are tuned for multiple bands...
Overall depending on how the stars are aligned I can't tell that one is better than the other- but both are hands and feet better than a stock antenna.
Yup. Although I haven't taken the pepsi challenge and compared this directly to many others(other than the stock rubber ducks), I'm pretty satisfied with the Diamond RH77CA.