As above it depends on the bit rate. The higher the better. 250 and up and I doubt you could even tell the difference. I had 2 Kenwoods and they both allowed for different settings for different sources. (1 for radio, 1 for CD, 1 for USB, etc.)
1. you can use vht nightshades 2.paint and clear mixture gives better results. It also is better to work with brand new lights. Don't know what it is about the old ones, but they don't turn out as good either way. I really don't suggest tinting your headlights. I would just buy the covers so you can remove them at night. Not going to look cool when you run head on into something because you cant see.