Am I missing much out my suurounds?

For starters, I have a somewhat large room. Probably best described as 30x30 square with listening/seating area roughly in a 15x15 front "corner". In the 15x15 area directly behind the listening area, I have R50's against the rear walls serving as the surrounds in a 5.1 system. So, the R50's are about 16-17 feet from where people are seated. The front soundstage is about 13-14 feet. Auddessey adjusts sound levels to accomodate this confuguration I guess.

I'm driving the surrounds from an NAD T755 AVR (100W continuous in surround mode). Front channels are seperately driven by NAD C270 amps running bridged to each mains LF posts (one amp per speaker LF). 755 L/R's drives the front main HF's.

My question is, am I missing a noticable surround experience because of either: 1) lack of true timbre matched surrounds; or 2) direct radiating vs. bi-pole/di-pole surrounds; or 3) combination of both 1 & 2?

I guess I initally thought direct radiators would be "better" due to the room configuration. I do think HT sounds great but maybe I dont know what I'm missing??

I have been thinking about FXi-A6s. But, am unconvinced it'll be noticably better. Or maybe a higher quality direct radiator speaker in the rear (of the room:eek:) would be better.

So, what say ye?