OK, have to put my 2 cents worth in here. I work for Crutchfield (some of you car & home A/V fans may recognize the name) so I've been selling car audio for about 15 years. Kicker makes some good quality speakers, as well as amps & subs. The new CS series speakers sound pretty good & are relatively efficient but handle quite a bit of power so they will do best with an amp. As for Sony, those wouldn't be my first choice. Most have treated cloth surrounds & aren't very efficient. Polk & Infinity are excellent choices - I've had both in my vehicles at one time or another. Currently I have Boston Acoustics speakers. Love them but unfortunately, BA is no longer making car audio gear; they've decided to concentrate on their home audio line.
Ann ("Older than springtime, younger than dirt.")
Molly, my rescued cockapoo, who loves camping
2013 Rockwood Roo 21SS
2003 Dodge Durango SXT w/full towing package