after comparing many choices of head units i decided i wanted a Alpine CDA-9813. the truth is i don't really know much about car sterio systems. i found this head units on the internet for $267 and i want to spend about $300 on a head unit. is this a good pick? if it is wut seakersshould i be lookin for? i have no idea how to match up speakers to head units. do I need an amp for front and rear speakers? if i don't is it a good idea to get amps? i would like to spend near $200 on the speakers if possible. thnx in advance.