[illab]

I agree with the check-call. If you led the betting on the river, you would get raised if the other guy had the flush or full house at which point you'd probably fold. If the other guy didn't have you beat he'd probably just fold. So by leading out and betting you'd either lose at least as much money as you did anyway if the guys had the better hand or lose out on an extra 150 if the other guy had a worse hand.