Alpine Type R vs. Polk GXR

    Alpine type R i have four sets in my jeep and i never had a problem. They sound great no matter what song i am playing. I havent worked with polk's speakers that much but the speakers i used i didnt like. I would go with alpine all the way.

SoundExplosion 

Yeah, I've got the Polk speakers now in my door locations running off of the stock head unit. They sound nice in the high range of the spectrum, but they are quite lacking in mid-bass/bass, since their natural cut-off frequency is 70 Hz. I am planning on putting 30W to them via an external Kicker amp and using an Alpine head unit (no internal amp). Will this "beef up" their sound on the low end or not?

Since the Alpines go down to around 40 Hz, this would obviously (in my mind) sound better from a low end standpoint. But will they sound as nice otherwise as the Polk's do? The 70 Hz cut-off frequency of the Polk's also limit my flexibility on the subs and where I want to set the x-over point (was planning on 80 Hz, but wouldn't mind going a little lower, maybe 70 Hz or even 60 Hz, if it worked out well enough).

Just looking for some options and whether I'm worrying over nothing.