It's also worth considering that different speakers have different resistance levels and whatnot (sorry, I don't have any more technical words... maybe TS or other electrical gurus can chime in)Ö
Short version: Stock speakers are matched to the power output of the factory system. Just popping in higher wattage speakers doesn't mean you can crank the system up to full volume and get "better" sound. You might get "louder" sound but if the head unit starts distorting as it's pushing its maximum power... you end up with ****ty sound.
Attempt with numbers: Say your stock radio is rated for 50W and can go as high as 40-45W before distorting. That's mated up to 60W speakers (if yer lucky) just to cover the max power and prevent owners all over from blowing out speakers. With that setup, it starts to sound like crap at volume 18-20 (our of 20) so people mistakenly pop in 150W speakers assuming the speakers are the limiting factor. The factory unit is maxed while the speakers aren't even close to being in their sweet spot.
But... from reading your last post, I dunno that this is the cause for your disliking the sound.
The internet says your head unit is Max power output: 50 watts max. The door speakers say: Nominal Output Power 30 Watt, Max (RMS) Output Power 300 Watt. And the rears... Minimum RMS Wattage 2 Maximum RMS Wattage 25 Peak Power Handling (Watts) 50.
I think you have two issues here:
1. The door speakers are not getting enough power to have the punch you want.
2. The rears are under rated and when you crank it up to push the doors you're exceeding their sweet spot.
However... I am NOT a pro by any means! Likely, neither are most of the jackasses at Best Buy or Car Pros
If you want truly amazing sound look on Yelp for a smaller pro sound shop. They'll cost more, but sometimes you get what you pay for xD
I hope some of the more experienced/knowledgeable folks can correct me if I'm wayyy off base.