Diamond antennas like the SRH77CA are designed as 2m/70cm amateur antennas. As such they will not perform optimally at higher VHF and UHF frequencies needed for scanner reception. Will they out perform stock antennas? Probably. Will they do well for the 700/800MHz range? Not so much. Any antenna for handheld use will be a compromise. Some are physically short. All have an uncertain ground planes and are heavily influenced by nearby objects like your body. The ideal scanner would combine high gain, broadband response and a reasonably short physical length. Not going to happen. The old RS 800MHz antenna and the current Remtronix are monobanders. They do work well in that frequency range. If that's where your primary interests are, by all means get one. If you want 30-50,118-136, 150-174,400-512 and 700/800MHz in one antenna I wish you luck. I've tried many. None are optimal. An external antenna like a discone is a better bet.