I would definitely look at the Morel Tempo Ultra 602 two-way component speakers. I have these in my car and feel they are the best upgrade I have ever done to my car audio system. Morel's are known for their ultra smooth tweeters and these do not disappoint. You can blast these things for hours on end and your ears will not get fatigued. In addition, after blasting your stereo for hours on end, your ears will not be ringing when you turn off the system. Try doing that with Focals or Kappas!
The biggest surprise was the midbass response. Huge midbass response with these, even though they are 6.5" drivers. When I had mine installed, I made sure I deadened the doors and I am sure this helped a lot, but WOW these things had a very nice punch! Drums sound absolutely amazing.
There is a build log on diymamobileaudio.com and these Morel Tempo Ultra 602s were used. The guy talked quite a bit about them. If you google search "Morel Tempo Ultra 602 review" you will find this build log. Check it out.
I bought mine for $271 on
Ebay. I was concerned about authenticity, so I talked to Morel (in New York, I believe) and they asked me to send pics of the box and of the back of the midbass driver. I did this and they replied that the speakers were, indeed, genuine. I think you can get a set for $265 on
Ebay, now.
At least, check them out. If you do purchase them, I am sure you will be very pleased with your purchase.
As for driving them, you have many options. They are rated to 120 watts RMS. If you are needing an amp just to run the front stage, the Alpine PDX F4 or the Arc Audio XDi 450.4 I think would do very nicely. Don't let the 15 watts difference between the two sway you too much. You will probably not hear the difference in volume between the two. If you are needing a 5-channel amp (to also drive a sub), look at the Alpine PDX-V9 or Arc Audio XDi 850.5. The PDX-V9 has greater crossover capabilities, but you probably won't utilize them unless you go active. And, if you go active, you will probably use a DSP which will have even more crossover abilities than the amp. Arc Audio and Alpine both make great amps.