About the whole Kira and Shinn speed thing:

Around 15 minutes into the episode, right before Rey calls Shinn back, Shinn is chasing Kira. However, Kira is clearly outrunning Shinn. Whether or not Shinn was using the "Wings of Light" thing, it does establish the fact that Destiny and S. Freedom have the same speed ablities.

Even then, when Shinn used his "Wings of Light" Kira was able to evade his first beam shot, and he blocked the second with his energy shield.

Weighting the evidence for everyone's agruments, it more likely that Destiny and S.Freedom are an even match....for the most part.