blk91tsi

Hey All, I am building out my first home theater but I have an odd shaped living room that, at first glance, doesn't seem conducive to a 5 channel setup. Due to the layout I am unable to place the speakers to the sides of the MLP. I have noticed that in the reference premiere user manual that there is an option to place them on the rear wall as well. I am looking for some advice on if it is worth it for me to pursue a 5 channel setup or just use a 3 channel setup instead. The wall in which the front speakers will be on is about 9.5 feet long but the rear wall that I could mount the surrounds to is only 7.5 feet long due to a bedroom door. The MLP is also centered on the forward wall, not the rear one. My question is, even though it is listed as an option to place the surrounds behind the listener is there any guidance on how far apart those rear speakers should be from each other or should they match the distance of the front left and right channels? Currently, unless they are mounted about 7 feet off the floor, I would only be able to separate them about 6 feet, the fronts will be about 8 feet apart. Also the rear wall is about 4 feet behind the MLP, is this too far? If it helps as well I am planning for the following: Front L&R: RP-260f Center: RP-450c Rear L&R: RP-240s If there are better options in my scenario for a rear speaker as well or if I am better off sticking with a 3 channel please let me know. Thanks