i've installed dozens and dozens of these. There are basically 3 different models, the IS77 is specific to ipod, the IS32 (one shown) is universal, and there's one more that's bluetooth. They work a million times better than the garbage fm transmitters. no static, no changing stations. It is still based on FM so you still lose some of your super low lows and super high highs. Most people probably wouldn't hear the difference.
when you buy them from best buy they include the labor. depending on the car you'll need 2 antenna adapters