Party 10/20. Help me with river play please

[StellarWind]

Checkfold is better than checkcall.

If you check Villain will read KQ as your best possible hand and value bet the flush and any ace. That's a large supply of betting hands that beat you.

Villain's losing hand range consists of 55-66, 77-JJ, QT-QJ. All of these hands are showable and beat the bottom two cards on the flop which makes them very poor bluffing candidates. It's possible he might value bet QJ/QT but most players that would try that would have raised the turn instead. Overall his supply of worse hands is quite limited and he is unlikely to make the bet even when he can. Bets from worse hands will be pretty rare.

Comparing the last two paragraphs the ratio of betting better hands to betting worse hands will be very high and 8-1 pot odds are not nearly good enough. Of course folding is a very exploitable play but it should be OK for one-off use. If you played this player constantly the answer might be different.

I'm less sure about bet-folding. Maybe the crucial question is whether he will call with small pocket pairs. It's hard to see why he should but many players hate to make this fold.