Phil,
I did not listen to the 703, for exactly the reason you mention. Though I'm sure the 703's sound amazing too.
When I heard the 704's, I was sold very quickly...no matter what CD I played, all different artists and genres, everything sounded exactly as I thought it should sound, and exactly like I wanted it to sound. Highs, lows, midrange...clarity, detail...they sounded perfect to my ears. I didn't see any reason to spend $3000 on something else when I was completely happy with the $2200 speakers right in front of me.
All of us, when we go shopping for speakers, hope to have "that moment". It happens when we find exactly what we're looking for, those speakers that make our ears happier than they've ever been. I had that moment with the 704s, and was comfortable ending my shopping right there.
I hope everyone else ends up enjoying their music as much as I do, because I know how hard it can be to shop....so many audio stores, so many speakers to listen to, all different listening environments. Everyone has a different opinion, and you can read a thousand reviews. It can be a little overwhelming. It's very rewarding when all the work pays off at the end.
Eric