I need a handheld vhf. Im deciding between the Standard Horizon HX471 and the HX500 because they are "multifrecuency" like FRS, AM/FM, aircraft band, etc... They are basically the same but the hx500 nas "nickel cadium" battery intead of an "Lithium-ION" one plus its $80 cheaper. I use to have years ago celulars with this type of battery and they use to get "memory" and not last long enough... Anyone knows if this has change? Any thoughs?