Trippen: Some stuff I agree with. It is waybetter to run new speaker wires throughout the car, big plus. I ran 14awg wires to my components and 10awg to the sub. My amp is only rated at 300 watts RMS but has 100amps worth of fuse and takes a 4awg wire so you know it puts out almost tripple its raiting (first gen Xtant 3300c).
Jl Audio makes excellent speakers! I have had them all. Infinity used to be the cream of the crop but now only their Kappa Perfects are worth a damn.
I have installed will over 2000 stereos and played with all of them. If you like rock music and live music then Boston is by far the best choice. Their pro series may run ya $250 a set on eBay but the only speakers I have ever heard that sound better are Infinity Beta (no longer available), Rainbow audios ($4000 a set), MB Quart Q series ($700 a set and they are not as loud or have as good midbass), JL Audios top speakes (also $800 a set but the tweeters are very harsh). Bostons will be the truest to the recording.
As for subs I have had them all. I am happiest with my current one though. I had JL Audio W6 and W7 but the Boston G5 I have now is unreal! I have a single 10" and the bass is phenominal! Deep, clean and tight. I lucked out cause it was only $75 but you can usually find them for $160ish on ebay. Mine is in a .5 cubic foot sealed box and tucked away where the factory changer sat. The sub is completly rebuildable too. There is no doubt that it is as loud as my old W7 but sounds better then my W6 did. Cant reccomend that sub enough!
Anyway Trippen, the older Premiers did have tighter tolerence caps in them and steeper x-overs as well as better D/A convertors but since 05 they have been identical. I was a Pioneer dealer for years in Maui and I heard this from the Pioneer rep and have confirmed this by taking apart several models. Only the warrenty is doubled but everything else is IDENTICAL.
Now the 9800 is a spectacular unit! I have run it up against a McIntosh deck amd a Nakamichi MB100 and there is no comparison. The Pioneer is 10x better. Takes a bit to get used to it as it really has no buttons (just a couple and a joystick) but it has more features then any other deck I have seen!