Went to Cex and swapped a computer game for a mint condition 4K UHD of Sam Raimi's Spiderman 2. Had a sneak peek and PQ is amazing (no pun intended).
Out of the ten 4K's that I've bought so far, this might be the best looking one. Highly recommended.
Also used staff discount and nectar points on a 4K UHD of Endgame from Sainsburys. My wife and I will watch Endgame this afternoon. We haven't seen it yet but unfortunately we have read quite a few spoilers (thanks internet!).
Those spoilers were pretty much impossible to avoid, I even encountered some in a random Star Wars thread.