Why? Rocket V2 as second stage/CF instead of V1b?

[gktamps]

Hi,
Wondering why some folks use V2 in a Rocket as the second stage, leaving 1/2 of V1 unused? Other than higher voltages than when using the stock V1a/V1b, is there any particular advantage or characteristic to this approach? More headroom, more drive?
Thank you,
Greg

[romberg]

One of the possible reasons for doing this is if it makes the layout cleaner. Might be shorter wire runs if the CF is on V2. Just a thought.

Mike