Few things monster cable or any cable for car audio is over rated, normal kicker or wlamart rcas will do.
Here are some links to some other options for speakers. Crutchfield marks things up so they are usually cheaper elsewhere anyway
http://www.woofersetc.com/p6133/DB65...t-Speakers.htm
http://www.woofersetc.com/p3372/165A...t-Speakers.htm
MM6501UM - Polk Audio 6-3/4" marine component speaker system
CXS64 V.2 - Image Dynamics 6.5" 4 ohm Component System
160V2 - Focal 6" 2 Way Component System
The bostons are good but here are some other options to look at, the first set are a bit lower than the bostons but still a good set. It is what I am running right now as I am going to trade my car in next year.