I have in one vehicle what I consider a fairly high power set of speakers, I'm sure they would handle 200 watts with no problem... but 240... that's pushing it.
And based on the fact that you like rock, rap, and loud, I think you definitely need a metal tweeter.
And if you are going def, you are going to be hard to please... I would not look at anything but a manufacturer's top line of speakers.
Since you are considering Diamond, I would save my pennies for Diamond D7... they are a set with a metal tweeter, state of the art cone material, similar cone layup as the precison power and the new Image Dynamics XS series, but made for high power... they fit the bill.