Television: Mitsubishi WD65737 DLP
Processor: Emotiva UMC-200
Amps: Carver AV 806x/Behringer EP4000
Mains: DCM TimeFrame 600 Center: AT 453C
Surrounds: AT 251.1 Sub: Danley DTS-10
Blu Ray: Panasonic DMP-BD655
But as flyng_fool said your room/seating is the primary factor ... If you have a small room, or the seating is against the back wall then 7.1 will be problematic and you won't lose anything using 5.1 (7.1 needs ample distance between the side-surrounds and the back-surrounds).
Like I said before, if you have 2 subs (even if they aren't the best out there) you will get a better bass response in the room, and better balance in the sound. Movies do really well with bass and having that presence or fullness helps more than having more channels.
For those looking into getting Energy speakers, or upgrading their current Energy setup, here are some reviews I've written that may help:http://www.tempestaudio.blogspot.com (haven't updated in a while, but include Energy Take Classic 5.1, RC-10, CF-70, and CC-10)
Hi, typically, what's the ideal distance between the sides and the back surrounds that would make the 7.1 work properly, can you elaborate please?