On the scale of 1 to 10 with 1 being the worst and 10 being the greatest, the 5.1 is exactly being to 5.1 in this scale!
Stereo sounds better than 5.1?
I don't think so !!! More speakers, if done right (ie. the right pre-amp), you get, better imaging, better clarity, better everything. Nobody that has any "Good" audio experience can disagree with this. If you do disagree, YOUR WRONG. I feel sorry for all you are missing. End of story.