1. What control mechanism do you think will suit you better and meet your aesthetic standards in your vehicle?
2. Lilliput or Xenarc models are the best. Price range is about $200-300.
3. If you've got the space, go for it.
4. Calculate the power draw of the system using one of many online power calculators, then make a decision for yourself. This FA might help you: http://www.mp3car.com/vbulletin/advf...iew&advfaqid=6
5. That might be a question for your local stereo shop.
For best results, make sure that USB hub is a powered hub. If it's not, you could very well have problems down the road.