I'm a little confused. In your intro you said that he slow plays too much but then you say on the turn that you know you have the best hand because he only calls.

I'm also not sure why you say if he has a straight draw it's only a weak gutshot. Why can't he be holding 35 here? I wouldn't be surprised if that's what he had.

You can't have played many hands with this guy so I think you are WAY too quick to be making and sticking so strongly to assumptions about the way he plays. Someone could sit at a table with me for half an hour, see me slow play a huge hand vs a maniac and think I always slow play. (This is not the case, I very rarely slow play)

I definitely try and get the money in on the flop so I'd raise closer to 1100-1200.

I hate the turn card because it makes a possible straight and possibly makes him play 57 harder than he would have before, making you overvalue his hand. Betting smaller is therefore fine.

On the river I check because I think he has 35 and is handing you the rope.
(Also the backdoor flush got there, this is of little concern though)

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