Hey Jazzcat - how are you finding your infinity's sound? Did you go with the +3 or +0 in the end?
Maybe it's where I am positioned but the rears do contribute to my overall sound experience in the car.
Funny you should ask. They will be installed next week when my aunt brings them up from the states. Will post a review then.
Glad you enjoy your setup. I approach the car audio thing much like my stereo setup (front L + R speakers) in my house, where the speakers are positioned in front of me. I prefer to hear that way. I never warmed up to 5.1 audio for music. Movies, that's another story.
I thought I'd give my 2 cents on how I feel about the rears. Most people assume those speakers are essential. Since many complain that the ford HU is underpowered, I noticed that the power seemed to double to the front speakers simple by using fade, and that the overall volume and clarity of the front two, seems greater than when all four speakers are being used . The HU is clearly splitting the power between front and back.
I suggest that anyone considering swapping the speakers, try both scenarios and determine how they prefer to hear. It's all subjective no doubt. No right or wrong answers.