What needs to be said in this thread has already been said by several parties including Wootware.
It is important to understand different perspectives in everything if you are seeking so-called enlightenment. I sympathise with your position, and I empathise with Wootware's.
The fact that your new screen is worse than your previous one confirms what Wootware have told you in that it is normal.
The comment of mine that you quoted was in fact in response to this juvenile writing off and judgement of brands in their entirely, that some people have resorted to.
No, and I am sorry that you've had to be on the receiving end of it. Just remind me what the price was, and model?
But, it is my personal belief that, if we are to be objective and compare the screen you bought to many others of the same, we would find that, while understandably unacceptable to you, you probably blew the extent of your backlight bleed out of proportion (along with your 'prima donna' nature

).
You had only ever witnessed one of those screens. And now your replacement is in fact worse. This is already proving that others are probably the same, as well as proving what Wootware have told you - that the screen is not faulty.
One may even find that you were concerned about your decision about buying LG and had a hard time going through with it, given what your father has always told you, and your disbelief in the brand. Of course, this would compound the problem of the backlight bleed because you would now be angry at yourself for not going with what you 'know is right', in a different brand.
Further I suspect you may be more used to CCFL backlit LCD, which is not prone to as many lighting problems as LED backlit LCD, which is why your expectations were higher. Or at least just very good iterations of LED backlit LCDs, with minimal bleed.
It will be an interesting test comparing to the Samsung you want. My advice would be to save for a Dell.