my brother works at an audio store so i have been able to hear many different speakers and compare the different head units. i have grown to like the clarion head units and have the new clarion 835 on order along with sirius satelite radio. the head unit is mp3 compaticle has a 24 bit processor and just seems kickass in everyway, i know the 825 was a good deck and this is an upgrade of it. as far as speakers go i would go either mb quarts or boston acoustics. both are really nice speakers. subs im a JL guy they rock. i havent heard a system that sounds better than 2 JL 13w7s with a jl 1000/1 amp to each. damn did it hit. but theyre W3s and W6v2s also hit very well and sound great. if your lookin more for cheaper subs/amps planet audio have surprised me a lot and sound great. i installed 2 planet 10s not sure wat model and a planet 300 watt amp. and it sounded incredibly for wat it was. sorry for being so long just throwing out some options for ya