Don’t rush as the new model year is just coming or not long been out.
Have a look at the TCL C745K 55″, its at he upper end of your budget but, will blow the others you have mentioned out of the water. It offers 120 local dimming zones something the other don’t, Quantum Dot and a much brighter 100onit panel, which is helpful for viewing in brighly lit rooms, plus alot more including voice.
Going head to head against the Sony X90l £1500)
https://youtu.be/pDds_7qO0lY (need to turn subtitles on)
The C845 is stunning but out of your budget and C645 sits below it and the P745 is a standard 4k TV