Thanks for posting your concerns.
In most cases, the clouding issues can often be resolved by adjusting the settings or having the unit calibrated. Since screen uniformity is inherent with LCD panels, and no two panels are the same, the chances that a firmware update fixing this isn't likely if you happen to have the issue. If it's what you feel is extreme, then (region dependent), we can have a tech take a look at it and fix it or you can exchange and try to see if you better results with a different unit.
"Extensive problems" on a world-wide forum can make small problems seem an almost certainty. Coupled with your experience so far, I can appreciate the trepidation.
Don't get me wrong - we want your business, but we also want you to be happy with your purchase. If you're not, do what's best for you.
I recently bought a series 7 LED 55" TV. From the first day I noticed a clouding on all 4 corners of the screen and a large spot off centre. This is very distracting and really cheapens the quality. I currently reside in Australia, but I can see this is a world wide issue with Samsung and seems to be a serious one. At $5,700 (that's what we pay here) I should be getting a perfect picture. I have seen some pretty brazen replies from Samsungs phone service to other contributers of this forum. I am worried that this will not be resolved and I want to know if anything is planned by Samsung to resolve this with a firmware upgrade - soon. If not I am returning it and buying another brand.
I also bought a BD-P1600 and on the first run of the Blu Ray version of "Sin City" the player's audio dropped out throughout the disc AND the picture froze twice. On playing the Blu Ray version of "Full Metal Jacket" the picture shuttered throughout the disc along with audio drop out. I exchanged it yesterday for the BD-P3600.
After reading all these common problems with the LED and BD players (both the 1600 & 3600) I feel I may have bought some VERY EXPENSIVE lemons and may dump my Samsung products. I'm scared to death to even try to hook up either to the internet after all I've been reading. It's unfortunate because I have older Samsung products that work just fine. It's obvious they have rushed them to market and we, the consumer, are paying for their mistakes.