Just looking around for speaker options and came across this.
Just for future reference, everyone seems to be getting really hung up on wattage. The rating on the speaker is just a safety limit. If you want to listen really, really loud, get something with a high rating. Otherwise, apart from subs, it's more or less unimportant.
For front speakers, the woofers probably want 50w each, mid/tweeters, barely 20w will be enough. So 75wpc would be absolutely fine. Most amps have this now, so just buy a) what you believe will sound best and b) what physically fits where you want.
(Not saying speakers aren't worth it at all, but from previous cars experience, I would say speakers are typically the last thing to look to... Get a subwoofer and DSP+amp for the standard speakers and - well tuned (which is the hard bit) - that will produce something an order of magnitude better than amp+speakers)