I have never done an ounce of research into anything that will let me talk on a cell phone hands free. I know absolutely nothing about them. I'm going on a solo car trip tomorrow and thought it might be nice to have one. So what's the deal? Is it all bluetooth, or are there still ones with cords out there? Is there one particular model brand that everyone goes gaga for? In case it matters, I have a Samsung M510 for Sprint. Thanks for looking!