I am pleased to say that I have just recieved my new system.  Beautiful speakers.  But before I actually can enjoy it, I guess I need to set it up first - unless I just want to use them as artwork, which they could pass for.  Anyway, on to business.  I purchased a 7.1 channel system.  The question I have is regarding the placement of the rear speakers (532LR).  I want to place them in the best position for optimal sound.  From what I understand, the side and rear speakers should not exceed 24" above the listening area and should be level with each other.  The sides (534-SS Bipole/Dipole) should not be a problem.  I can mount those in any height range immediately to the side of the listening area.  I purchased the Omni 20.0 Wall Mounts for the rears.  The original thought was to mount those up near the ceiling, which is about 8.5' high (or about 5' above the listening area) and point them downward at the listening area (which is about 3.5 feet off the back wall).  The reason for mounting them near the ceiling was for asthetic reasons, plus there is artwork on the wall immediately behind the listening area.  However, the artwork can be moved and I can mount the speakers on the wall dirrectly behind the listening area about 2 feet above the seating location if need be.  Will I lose anything in terms of the quality of the effect the rear speakers provide if I mount them 5 feet above the listening area and point them downward versus 2 feet above?  Keep in mind, the listening area is fairly close to the rear wall at about 3.5 feet off the wall. 

Thanks in advance for any advice!