Dennis,
I really think you should gauge the neckline depending on the weather. If it is chilly outside, then I would go with the higher neck...if you are not afraid of showing a little cleavage when it is chilly outside, then go with the v-neck....
Seriously now, my Wisconsin cheesemate, with all of the more pressing questions you should be concerned with....like what kind of beer goes best with brats...I am surprised you are even worried about fashion in this day and age...