Find exactly what you want first. Search around a bit and then compare prices. Crutchfield has been my choice. Their prices may be just a BIT higher, but their customer service is second to none and they have a "Scratch & Dent" section where you can almost always find something where the box has been opened or it has been returned because the person didn't like it. I got my Clarion unit from Scratch & Dent and it's perfect. Plus I saved around $40.