It depends on position. If you dont have position and you want to control the pot size, than it is tough to throw out an info bet, because you are starting to put yourself in deeper. Here, you may want to relegate yourself to throwing in moderate bets and then just making a decision based on strength if he pushes back. In position, definitely push and push hard if you are strong at all. This is good for information gathering and controlling the pot.

Even though you are throwing in the extra bet when in position, you are severely limited the chances that he pushes back at you unless he really is much stronger. In that way you've controlled the pot and have the option to check on the river if you like.