Just wanted to share my experience of invoking the John Lewis 5-year warranty.
Bought an LG G1 in Oct 2021. A week ago (4 1/2 years into 5yr warranty) a black vertical line appeared. Contacted John Lewis who I purchased it from, and engineer came over next day, identified as panel fault which a) he could replace for free, or b) John Lewis could replace set/compensate me - up to them.
JL contacted me and offered £1,399 voucher - £100 shy of replacing (IMHO) "with the nearest equivalent product" (the G5). I wasn't trying to get more for the sake of it - but I just wanted another LG G-series. If they offered me a still boxed G1 I would have taken it. But all they have is the G5. So I pushed back a lot on the extra £100, but they wouldn't budge.
So I took the £1,399 - tbh, a good result, I go from G1 to G5 for just £100 after over 4 years and get a new 5 year warranty. Just a little miffed that their promise of "If we can’t repair your item, we’ll replace it with the nearest equivalent product." wasn't honoured.