I have the A550 (probably the same thing)
Speaker doesn't sound terrible but they are feeble. I still use them for OTA TV viewing only.
SD rendition is generally not that good and BAD if you need to use a stretch mode that zooms (like blowing up 'stamp' 16:9 SD content to fill the screen = terrible, no issue on my other plasma doing the exact same thing)
I am quite happy with mine for what I use it for.