i was going to post this same thing.
you need to seal up yours doors and pump 100w rms into them to get the mid bass everyone talks about. they are pretty awesome for the price either way. thats what i would go with.
i'm actually thinking about going to them from my alpines

 

depends on how you look at it. If you believe that more power to your speakers gives cleaner, tighter, more dynamic sound, then the fact that you can leverage 2x the power from the same amp as compared to a 4ohm speaker would indicate that you should get better sound. In my case, it was better, because I could use the same amp and deliver 100watts + into the 2ohm speaker, as compared to only 50 watts to the 4ohm. Immediately it was louder, cleaner, punchier...much better midbass with double the power. From a strictly 2ohm vs 4ohm, all else equal...4 ohm is supposed to be better sq, but it was not apparent to me when both sets were at the same power level, in the same vehicle with the same songs. To be fair, they were similar speakers, not the same ones, but I was listening for clarity, distortion, and loudness...I expected tonality to be different given that they were different speakers. Anyway, I thought the power advantage easily out-weighed the impedance issue. Another thing to consider is that I didn't want to change amps, as I had recently gotten the RF amp. If I was doing an entirely new system, then I would go 4ohm, and get an appropriate amp to power it fully.

 

thank you veeman for this explanation and thank you everyone else seems i have some work ahead of me