I would have to say Infinity Kappa Perfect 6.1 all the way. Give them a shot. I have them in my car. They are not cheap but they are worth every penny. I love mine. Most importantly, so long as they are equalized right, you will never having a problem with highs being drowned out by the lows. Wonderful product, not many compare, a definate recommendation. Get a Rockford Fosgate 200.4 to power it. It does great things for me. And good luck.
i would never go with infinity speakers they are good but not worth the money they coast..i would recommend either diamond audio for exremly crystal clear sound or you can go with Momo audio polk's top of the line stuff...if you really want to spend some money you can go with ample audio all the way through that is some great stuff. for an amp it is all gonna depend on what kind of speakers you get if you get speakers that can handle 100 watts run a 400.4 amp and run 100 to each speaker.that will sound awesome.
focal, mb quart, crystal mobilesound, alpine, infinity, diamond audio, boston pros, image dynamics, and eclipse are the ones that come to my mind. to run them, i'd use and alpine, eclipse, phoenix gold, or jl amp.