Which Burnside to use

[fiatdad]

I was looking at Accurate bullets Burnside bullets for my 1861 Burnside.
They have 3 available here are the descriptions,
https://accuratemolds.com/bullet_detail.php?bullet=56-390A
https://accuratemolds.com/bullet_detail.php?bullet=56-390B
https://accuratemolds.com/bullet_detail.php?bullet=56-450B
Which one may be the best one to use? I am thinking the first with one large
grease groove may be best, but the others have a larger bearing surface.
Thanks
Nick