As for rear fill, let me ask you this, Harley. What percentage of the time out of all of your driving do you have passengers riding in the back? I wouldn't waste the money on rear fill if no one rides back there more than 70% of the time. That's money that can go elsewhere to greatly improve the quality of your system, especially on the $1K budget. If you're the main listener you don't want to pull the stage behind you. A front stage can easily fill a whole cab.
There are only a few reasons I'd put rear fill in a truck:
- If I had a 5.1 head unit with access to 5.1 material
- If passengers rode with me more than 60/70% of the time
- Competition
I have a set of amped components up front and rear speakers deleted. I have people ride with me quite often and all of them agree it gets plenty loud for them when they're in the back. It can get as loud as you can stand while retaining quality. What I'm getting at is that I see no reason to spend money on rear fill, especially on a budget.
I hate it when my rear speakers are turned off... The truck sounds empty...

I've been more than pleased with my Alpine setup... Great sound quality, not the loudest, but I can drown out all road noise... And that's perfect
Rear fill does make a difference... I actually prefer a little more rear bias myself...
And never pick your stereo setup for passengers... Only do it for yourself

) for speakers the mids we used I forgot the spelling(cios?), Tweeters were poly/audax,JBL 6"X9"s and either Kicker,Orion or Cerwin Vega subs(some rear deck ported some boxed and fireing forward.