I thought you had mentioned the quantum X, but realise now its just the standard P series.
The Vizio P series, Hisense H9G and TCL R635 are really the main options all around the same price, all have similar overall quality. The Vizio is a good choice for gaming since it has HDMI 2.1 features. Its smart TV platform however is poor, local dimming performance is average, which will only be a downside if you plan to view the TV in dark conditions.
The TCL R635 has better smart TV, but still doesn't have great local dimming, which like the Vizio will mean it won't look as good in a dark room.
The Hisense H9G is probably the best overall TV of the three, but it has a known problem with red blur that appears in certain content, so you may find if you end up having this problem you'll want to return the TV.
I own a H9G, its a cracking TV, just not sure I can get over the blur problem, but at the same time I'm pretty sure I would have a worse overall TV if I had gone for the other options instead.
Perhaps instead consider raising the budget to an OLED, the Sony X950H or Vizio Quantum X to make less compromises with picture quality.