Recommendations...
Do some reading on the soundstage within a car, realise that 6x9's are awful (even moreso when combined with a sub), and then go for sound quality and not volume/bass.
You'll get this a lot in here. So brace yourself
The benefit of 6x9s is volume, and as a budget, all in one solution they will 'do'. However, they will often bottom out too early to provide any low-down oomph whatsoever, and too late to intergrate well with a good sub setup. Used with a crossover, they make excellent sound fillers at volume though
I recommend you upgrade the front components first (this'll offer better volume levels and sound quality). However, you should bear in mind that any headunit at that price range and will power them poorly. They'd be best amplified.
A good solution would be the headunit and front components initially. Followed by a multichannel amplifier and a sub (run the amp with two channels in stereo for components, and two bridged for sub).
You'll need to check your dash, but running USB into the glovebox will probably invlolve a little drilling, did in my 'scort. Though not in a suzuki I did for someone.
Running an amp isn't as simple as whacking it in. You need to run live from the battery, through the car, to the boot, and fuse it near the battery. You then need to ground the amp (WELL) in the boot, usually on one of the bolts of the suspension strut. Then you need to run a pair of RCA leads down the other side of the car from the back of the HU to the boot for every pair of speakers / sub you'll be running.
If you want to go the 6x9 route, my JBLs didn't do me too bad, you'll be able to use the standard wiring (as long as the car has rear speakers) with a little modification. My advice is spend money on the head unit, I've got a alpine 9880r, and the amplification is so good on it I can barely tell the difference between the HU and the Orion-2400 amp I use driving my components.
Can't help with brands at that price range though. For speakers, go Rainbow or Hertz, for subs, JBL used to be the daddy when it came to budget equipment.
If you want setup help give me a shout
Ant
