Unless you need to go with a bigger size that puts an equivalent OLED above your budget, OLED 100%. Doubly so if you are coming from a Plasma. At your budget, and barring any edge use cases like watching in direct light or 8-12 hours a day of static content displayed (channel logos, HUD elements in games etc), there is no reason not to go OLED.
All currently available OLEDs have panels manfactured by LG Display, so any OLED is going to give you an idea of how good the PQ is in general, but specific implementations will differ in terms of motion handling, picture processing, OS and other OEM specific stuff.
See below for a well-unscientific comparison between a Panasonic FZ950 (2018 OLED) and a Sony X950g (2019 LCD/LED, one of the better ones) in-shop. That is a rather extreme case (white text on black background), but illustrates a big point of difference between OLED and LCD/LED that may be quite apparent to you after enjoying a Plasma for a few years: backlight blooming.
The higher range Samsung Q80/Q90r will do slightly better, but not unnoticeable better. And honestly, the only Samsung QLEDs worth considering are not comparable price-wise to competitors unless you have very specific use cases. The Q60 is not worth considering at any size.
As others have said, you missed the boat on Boxing day prices, but if you can wait, in the next couple of months you may get close with run-out pricing towards April or a special sale ie. Waitangi day.
How far away do you sit from your main viewing position?