[Mr.ac]

Sounds like you need to take a trip to your local car audio store.
Those would sound great regardless. You don't need to buy another amp. Your current one would do the job just fine.

As for the more expensive model, yes it would be a better speaker.

As for the bass, that's going to depend on countless factors.
Ideally you want that mid bass punch on the 6" woofers. Let the sub do the deep low bass.

But then again one of those factors is your crossover point on your amp. You want a nice flat mesh with the woofers drop off point and the subs starting point. But eh that's a deep spiral of audiophile junk.