Looking for some thoughts or help, getting ready to put intercom/radio kits in my cars, and wondered whether there is a noticeable difference in quality between the Rugged Radio 660+ and the PCI Trax. I understand that the the 660+ has what is referred to as a high-fidelity amplifier but still delivers mono sound, whereas the Trax delivers stereo. I'll be doing helmet kits and not headsets, so if anyone has opinions, please share. I have sound systems already for when we want music while sitting around, but would like in car and car to car when riding. The price difference is significant, even more so when Rugged is offering their specials, such as now. I'll be putting them in a X3 Max and YXZ, thanks in advance.