Serves aren't my strong point, and I think my serves are about equal with the two racquets. I can probably get just a little more pop out of the Donnay 100, but the power difference isn't really noticeable enough for me to worry about. I can easily switch between the two racquets without much of an adjustment period at all. As a side note, I string both with multis and currently have Biphase at 57 lbs in the Q5.
I have to admit, I'm pretty excited about the upcoming Yonex VCore Xi racquets. I'm a former RDS 003 player and loved the VCore 100, too.