Well if you're looking for SQ and you're not running surround sound, I would say nix the rear speakers. When you go to a concert you don't turn around to listen to the band...

If you are set on getting rear fill, I see that both the Kappa and Reference series are 2 ohms, I'm not sure if that will have any bearing on your amplifier or deck choice.

Another suggestion out there (I know there are few 3.5" let alone co-ax versions out there, I haven't heard any complaints about the MTX TDX3502's which meet your 92dB sensitivity and have a 1.5" mounting depth and they're 4 ohms to boot.

__________________
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reQ5
TDX6802
TS551022
TE801D
TE604
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