from personal experience....

be very careful running steroids at 20-25%
the more fat you have the more aromatase you have
aromatase converts testosterone into estrogen.

you can actually be counter productive and cause more belly and breast fat to accumulate as estrogen levels rise.

I ran my cycle at 18% against everyones suggestion when I started. I ran Letro .25 ed to whipe out estrogen, not just surpress it like adex. It probably inhibited my gains a little but it got rid of the aromatase so I didn't have to worry as much.

I did drop about 3% and put on muscle, but the cycle was not the be all and end all. I finally dialed in my diet and am fasted cardio and then was down to 10% fairly quickly.