Is it worth changing a fuel pump or distributor preventively?

I drive a well-maintained 1998 Pathfinder with 140,000 Miles. It has been totally reliable until it recently gave out on me, and I had to have it towed to my mechanic. When he got to it, it started immediately and ran like a champ. It has been doing so ever since. He suspects either a fuel pump or a distributer. Since both are relatively expensive, he did not replace either one and told me to drive it until it happens again. I prefer not to do this as I don’t want to get stuck again. Any advice?

I would consider the fuel pump as most likely the cause because if you don’t want to change it now, carry a rubber mallet in the truck. If it refuses to start, whack the bottom of the gas tank with the mallet. If it restarts it is the pump.