I'd guess the odds would be in favor of latter. With a runner at third, the runner could score on a sac fly, wild pitch, squeeze play, bobbled ground ball, etc. It definitely puts more pressure on the pitcher and fielders. Historically, there is a 66% chance of scoring with a runner at 3rd and 1 out. At least one of three straight .250 batters will get a hit 58% of the time (although considering walks, errors, etc. the real odds are probably 60-70%)