Kenwood doesnt make the greatest amps...but they arent asbad as pyle either...
I have had mine for 2 years, and who knows how long it was in the car prior to that...and i have never had any problems at all out of mine...
they dont do rated power though...
I,ve had a chance to play with the new Kenwood amps.
The 9152 will do its rated power of 500 @ 4ohms and 900 @ 2 or 1ohms(regulated)
It also has CEA certification backing that up.
I think its a great amp for the money and would recommend it.
As for chris'es Kenwood KAC-929 here is a reveiw by Brian Smith of Car Sound & performance
The KAC-929 is a two-channel amp with power ratings of 150 watts x 2 or 460 watts x 1 into 4 ohms and 230 watts x2 into 2 ohms. Features include a variable low pass filter, switchable bass boost, an expander, speaker level inputs, and fan-forced cooling.
Performance
The KAC-929 performed quite well on the test bench. While it didn’t post any surprisingly large power figures, it did meet or exceed all of its real power ratings with a minimum of fuss. The amp ran through our entire line-up of tests without a hitch, which generally indicates a stable, sensible design. Efficiency at 1/3 power measured an impressive 39 percent and overall, there’s a lot to like about the performance of this amp.
Distortion at Rated Output @ 1 kHz: 0.02% THD+N @ 460 watts
Output Power (resistive) minimum output 20 Hz to 20 kHz @ 1% THD+N, all channels driven into 4 ohms: 155 watts x 2 @ 14 volts, 127 watts x 2 @ 12.8 volts, 81 watts x 2@ 10.5 volts
Output Power(resistive) minimum output 20 Hz to 20 kHz @ 1% THD+N, all channels driven into 2 ohms: 214 watts x 2 @ 14 volts, 176 watts x 2 @ 12.8 volts, 111 watts x 2 @ 10.5 volts
Output Power (4-ohm IHF Reactive Load @ 60 Hz to 1% THD+N): 545 watts