The only way to tell how the speakers sound, is to listen to them. Everybody's ears are different, and you may not like the sound of a speaker that your best friend loves.
As far as build quality and power handling are concerned... a stock speaker is NEVER going to be as good as a high-quality aftermarket speaker.
BTW, I do not count Kenwood on my list of high-quality speakers. They are better than most, but not "high". Neither are the Polks for that matter... or most other brands sold by large retailers such as Crutchfield, Circuit City, etc.
Hehehe, enough ranting from me... Go by what YOUR ears tell you, not anyone elses'.
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1989 Mustang GT, Charcoal Gray w/Titanium, 71k miles
13.413@108.95 -- 2.159 60ft. on SZ50's
FMS 3.55 gears, Tremec 3550 w/Hurst Comp. Plus shifter, Steeda alum. quadrant, FMS HD clutch kit, Compucar N2O, 16" x 8.5" O.Z. Italy Monte Carlo wheels with 245/50ZR16 Firestone SZ50 tires, BBK 1 5/8" Jet-Hot long tubes, Dr. Gas X-pipe, Dynomax CVX cat-back, Factory Five upper and lower rear control arms, SVO pulleys, Accel 300+ ignition and plug wires, K&N conical filter, 75mm Pro-M, '93 Cobra rear valance, Auto Meter gauges, '93 Cobra intake, FMS 65mm TB, Kirban adj. fuel pressure regulator @ 42psi.
Chad's Virtual House