Luckily managed to find some techy-minded friends with Panasonic BD55, Sony 550 and Pioneer BDP-55. Tested all on a 5090 Kuro with Yamaha Z7 and M&K Xenons with SB1250 sub. Panasonic did have the edge over the Sony (unilateral opinion) when bitstreaming audio through the Z7, or coming straight from bluray. Better imaging, colours and soundstage. Then we looked at the Pioneer BDP-51 and it really did blow the others away. Quite simply much better picture and sound. More drama, more filmic, clearer dialogue and richer natural image. In fact, just like the WHF review states 'refinement and finesse'. CD player excellent too.
Ethernet not important to us as can burn upgrades to disc, plus not interested in low qual extras. At £325 for the Pio 51 (and fast running out apparently), we put our order in! Worth noting that this was all viewed on a 50" screen, and a 9th gen Kuro at that, so Pana 55/Sony 550 might be absolutely brilliant for smaller screens but the price differential is much reduced right now, so temptation kicks in. Enjoy.
p.s Glad no-one had a high end Denon or Pio for testing!! Daren't see what that looks like on a Kuro or proj.!