Seen this in store yesterday at Richer Sounds, after a lengthy discussion with the sales guy it was the set I kept going back to, but was above my £800 budget having originally gone in to look at the £599 700B model.
Having looked at them side by side the 750B did seem a big step from the 700B, refresh rate on this I believe is 120Hz and the 700B 60Hz.
Picture was really good - Anyhow today I see that Currys are offering £50 off any TV over £599 so it comes down to £779 and you still get a 5 year warranty included, so probably not worth asking John Lewis to price match as Currys is only 5 mins down the road and John lewis a good 30 miles away.
Use code TV50 to get this price online or instore
Could try Quidco as well @11% but unlikely to get both,