I would have been inclined to bang in a Stopperbet similar to RF on the river for fear of him making the perfect river bet and me scratching my head wanting to see if he's telling porkies or not...
My problem is looking for excuses to call and any dodgy bet here would have me trying to look him up
RF got the information he needed with the $25 bet and it's always good to know that regardless they have to show their cards because someone is all-in. Players are aware of the fact they ave to show and it makes some reluctant to bluff for fear of being exposed..