I don't disagree. In fact, if all ones seats are within the primary dispersion window of the the SCL-6 (either because the furthest left seat is not too far off axis from the front right speaker, for example, or because one is using an angled baffle wall behind the screen) then I strongly agree that three of these up front, vertically positioned with the tweeter at ear height, are going to be VERY NICE.
With both models, in a multiple row theater, I would be a little worried, since the vertical dispersion is so narrow. And I am still not a fan of manufacturers not supplying a backer box, and just assuming the stud bay dimensions will be acceptable.
Thank you folks for the helpful insights!
Listening/viewing angle
My room seems to naturally drop the front/main row around "SMTPE closest" distance on a 150" screen, so about 47 degrees, and to maximize space plus since it's typically my wife and I and we like to stay close I'm going with a narrow 3-seat low-back reclining sofa. Figure speakers right within the edges of the screen will create a 45 degree spread. From the left and right seat I figure that puts the listeners at maybe 40 degrees from the opposite speaker?
Room reflections
My intent had been to control the near wall reflections as my assumptions was that these were the earliest and therefor most important to reduce. I hadn't considered as much the issue of lighting up the opposite wall. Are my assumptions incorrect here?
Non toed-in speakers/additional options?
In my particular situation the screen wall is an existing wall shared with a basement pantry and tool closet. Because of this I have a lot of leeway on the types and depths of speakers I can use. I wanted to retain the existing flat wall as a baffle wall, but It's not critical that I stick with shallow 4" deep in-wall speakers. It also isn't critical that I enclose the backs of the speakers. The primary attraction of some in-wall speakers, like the SCL-7 and the Monitor Audio IDC models, is the built-in ability to have an offset while keeping flush mounting on a flat wall.
I had been under the impression that infinite baffle setups are preferable if they are practical for a situation, and in my situation I can leave the backs of the speakers completely unenclosed instead of in a stud bay. I thought this would have benefits in less internal reflections within the speaker, less resonance (ports/etc), and less back pressure so the drivers can move more quickly and freely. Is my thinking wrong?
Alternatively since I don't need a shallow depth, I could consider full depth conventional speakers (say 12" or less) mounted into the wall, so long as they are sealed or front-ported.
Vertical dispersion/second row
I'm planning to optimize sound for the main row as the second row will be truly "secondary". As long as they can understand the dialogue and enjoy some subwoofer drama, I'm sure everyone back there will be very very happy. My plan is to have the tweeters vertically centered behind the screen, and first row eye level around 1/3rd of the way up the screen.