i was planning on putting a new system in my grand cherokee. right now i was thinking of going with an alpine cda-9831 head unit, mb quart qsd216 Qlogic components up front, jl 12w6 sub w/ jl 500/1 amp..and a jl 450/4 amp to power the components and rear speakers. what would be a good make/model of speaker to put in the rear?? i was thinking infinity kappa's but if anything else would sound better than please help me out. also if anyone thinks i should change anything in the setup listed above let me know. any input would be appreciated. thanks