You're welcome. I'm rather lucky because as well as RS we have HBH Woolacott's who are excellent but only have shops and deliveries in Cornwall and Devon.
With regard to what you are looking for and noting your comments about inbuilt sound quality I think your possible choice of the Sony Bravia 8 II is a good one but I'll relate our findings when we replaced our older LG set a few months ago.
Like you we wanted the best picture and built in sound quality as my wife was finding it difficult with dialogue and I have hearing aids due to moderate hearing loss. At first we chose the LG G4 set but found we didn't get on with it due to distortion on sound. Fortunately HBHW accepted it back and we went to choose a replacement. We were very impressed with the Sony sets with their screen actuators including the then Bravia 8 and their then top model which my wife wanted to buy but we hit a snag as that had feet at the extreme ends of the set which were not movable so it would not fit on our corner cabinet and I note the latest Bravia 8 II is pictured with feet at the extreme ends so this might be worth checking if it matters to you. In our case we then compared the then Bravia 8 {which did have movable feet} with the Panasonic Z95A which had a central foot and had attention paid to sound quality with effectively a sound bar built in as well as a brighter screen. In the end we bought the Panasonic and were very happy with it.
Since then the Panasonic has been replaced by the Z95B which, according to Panasonic, has improved sound as well as the latest OLED screen. If you ask RS for a comparison of these two, Panasonic and Sony, I'd be very surprised if you didn't find one to your liking or even, like us, find it a difficult final choice as they are both excellent sets and well built.
One final thing, the Panasonic has a Freely tuner rather than the usual Freeview or Freesat and this works off the internet although you can use a normal aerial as well which will give some channels not yet provided by Freely if you need them. In our case we mainly use Sky Q so it doesn't make much difference and Freely works fine although it is obviously still developing and expanding its range and features.
Sorry for the long explanation but hope this is helpful.
Roger