Bear in mind that most companies are specing amps at 14.4 volts and you won't usually see that at the amp.
It also makes a 12 V rated amp seem less powerful than it really is.
All I can find on the kicker site is a rating at 1% THD, which is not that useful.
We are left to guess at useful power unless you can get more info calling them.
They rate the 750 at 375 watts into 4 ohms, which is the impedance I found on the kenwood speaker, though they carry a lot of 8 ohm stuff.
But that is at 1% distortion.
I think that makes the kenwood the more powerful amp.
The kicker is also a mono amp, which can make it cheaper to make, but that is all it can be used for.
The Kenwood is a bridgeable 4 channel amp, always easier to sell.
Since you don't quote prices, I can't compare there.
All I know about kicker is that crutchfield has had good experience with them.
The kenwood amp probably has far better signal to noise specs than the kicker, which matters a great deal to me.
It may not to you, but differences are audible.
I find contradictory specs listed on these products.
Many say kenwood amps are overpriced.
Most of my car equipment is kenwood, about half being excelon.
I have never used kenwood speakers though.
I have a kenwood amp 70-100 w/ch which is bolted in my race car and has survived track use with no issues.
Same with the cd changer, though vibration will destroy any loaded cds.
(It was not shock mounted as I would have done it.)
Kenwood strived to publish conservative amp specs long after others quit.
They would often rate hifi specs at 10 watts, higher distortion at 12 w, and the 1% level at 15 watts, giving people the range of misrepresentation involved in car decks.
I only use stereo speakers because all spatial imaging is lost with bass in mono.
This may not matter to you for sound reinforcement, but it does make a difference even for this application.
It is worth noting that most people buying losermobile car stereos seem to be interested only in the wattage the speaker can burn up, not the audio produced.
I ran across someone bragging about an FI BTL, which seems to be such an awful piece of crap that the company lists no sensitivity specs whatsoever.
They claim it will absorb 2000 watts though.
So most drivers are being made less efficient and rated at higher wattage.
Also an efficient driver that can handle more power usually becomes less efficient, mostly due to weight and stiffness.
A longer throw can also destroy efficiency.
It is better to get a very efficient driver and a smaller amp, if volume is the priority.
Also total consumption of power by the amp may vary a lot, if that matters to you.
The kenwood driver is rated at 90 db sensitivity which is mid-pack.
Since you have it, I would get the best amp you think you need and can afford and see how adequate it is, and add more efficient speakers if you are unhappy.
Once you have 70 watts or so, more power does not make as big a difference as you might think.
Also, many speakers power ratings are vastly overstated.
An efficient 15" driver often will not take more than 200 watts to produce it's maximum level.
Newer pa drivers are built for higher levels, but there is always something lost.
dB and Power (20dB = 100x)
When talking about power, 3dB represents a ratio of two to one or a doubling of power.
* Thus, a gain of 10dB would represent a ratio of ten to one for power - so 10 dB be 10 times the power
* A 40dB power gain would be 10,000 times the power.
A sample of some high power, and high efficiency drivers.
http://www.kenwoodusa.com/Car_Entertain ... /KFC-W3011
http://www.kenwoodusa.com/Car_Entertain ... iers/X600F
http://www.kicker.com/sites/default/fil ... %20web.pdf
http://hyperphysics.phy-astr.gsu.edu/hb ... nd/db.html