It's going to depend on the circumstances as well the players and what I've already seen from them. I was playing a game the other day, where a player had limped in front of me from EP. I raised to 4x with jacks from middle position. The button shoved. I was going to call. But when the player in front of me called, I decided to fold. The player in front of me turned over A-9 and the player that shoved from the button turned over A-7. I was a little pissed at having folded jacks to two ace-rag hands. But now I had an idea of what kind of hands they were willing to go all-in with. Later, I put that knowledge to use, taking one of them out when he shoved on me with a weak ace against my A-Q. A little while later the other shoved all-in with a pair of sixes and I took him out with a pair of 10s. I'm not sure I would have made either of those calls had I not already seen examples of their play when I laid my jacks down to them.