The average UU stolen it's 2% per 15 turns raid.
The max is like 3% and the min like 1%. This may vary a bit, but the real values should be very close.
Not sure about strike power vs defense .... I had like 8 mil strike vs 0 defense, but I don't think this will really change things too much.
Have fun raiding
PS - I did returned the UU.

