Those JBL's are good speaker, your not going see the true potential without a good amp behind them, not necersarily large in power. Find a 70 or 80 watt (RMS), 200 watt(peak) per channel to run them and your golden. I don't really know much about Kincker other than they make quality products in the mid and upper lines of everything they make. Another one to check out is Ecilpse, they make amazing sound, the best I have ever heard with little power, even straight off the deck. I have them in my Blazer, and have had them in other vehicles in the past.
Check out this link to their speaker lines. The point series is the upper most line and a bit more expensive, plus they don't offer the front size for your application so you would have to change it or go with something else. I have the Integrated series in my Blazer currently, they are great!!! They have both frt. and rear for you too. Just a suggestion, a bit cheaper than JBL and I THINK a better sound too. Good Luck.