Thanks for the replies, Gel, and yes I did assemble the stand on the E6 with the four M4 bolts supplied. It is only when you touch the stand that the screen wobbles, but of course it does need dusting from time to time and I can't help thinking that in time this slightly flexible stand joint is going to wear.
The top of my screen moves about a couple of inches when touched - I think you had one of these models, did yours move this much? If this is common to all E6s, I suppose that LG must be confident that the stand joint is secure.
On another topic, the out of the box picture is quite poor and so would benefit from calibration. I live in East Anglia, can anyone recommend a good professional calibrator that covers my area?
Thanks again for the help.