Well I appreciate all the inputs you're all giving. I first wanted to improve my sound quality, but it the end, it turned out that my speakers installation was far from being optimal.

you know, to compensate the bad speakers positionning I had to tweak my amp, like giving a boost to the center channel, and a +8-9db to rear speakers to hear anything from them. It's probably giving bad results.

As soon as I get back from my business trip (tomorrow), I will definitely buy a new 'center' stand and order the metal brackets for the front..

do you guys think I will be fine with the brackets included with the QS8 or I need to order full brackets for these too?

these brackets are really expensive..