Well, if your wanting to go aftermarket, don't get wally world speakers, though they are OK, just don't expect much. If you get aftermarket you should also invest in a proper amplifier to power them. A typical radio outputs 50w*4 MAX, usually 20w RMS, and most aftermarket speakers that are of good quality are 75w RMS. I have a set of Clarion SRQ6933R in the back with a pair of SRQ1722S up front. Speakers alone costed me a good $400 though, but they are very nice speakers with great highs and good mids, they are being pushed with a Clarion XC6410.
In the end, just amps/speakers cost nearly $1000 for a half decent setup. But if your looking for cheap, I personally enjoyed the Pioneers when I was younger, just remember, 6x9s and front speakers are meant for highs and high-mids, nothing low. Once you start pumping lows and lower mids through them, your going to blow them.
Oh, and umm... PLEASE stay away from ANYTHING that says SONY, walmart version or legit dealer version, SONY is nothing but over-rated (literally) trash, even the wally-world junk ends up being of better quality half the time.
I also hear Kicker makes some pretty decent 6x9s, just gotta remember, don't let the head unit do all the pushing, get a proper amp for any aftermarket speaker added to the system.
Just bought all that this year too as I am starting to get back into some local competitions for SQL.
