50fps amounts to nothing as far as real world effects on game go.
Choose the one that is most accurate and take that to the field with you.
I have no experiance with these bullets in .243 but keep this in mind. I found the 55grn V-max's to be a marginal coyote round, to many splashes on front shoulder/leg shots. The V grenade is a mush more explosive bullet, and while I havn't seen the results with my own eyes, I'm told they perform much worse on coyotes then the V-max's do.