read a study they did on people given 40mg or 80 mg x 12 weeks.  40 mg dose gained 3 pounds, and the 80mg dose group gained 5 pounds.  40mg group had a 33% decrease in HDL, and the 80 mg group had a 50% decrease.
now, keep in mind these people did not work out at all.  maybe if they did the 80 mg group could have gained 10-12 pounds... who knows.
the HDL decrease is kind of alarming though.  therefore, i think if i was going to use it with 500 mg test, i would prob use 50 mg for just 4 weeks.  maybe i will only add another 5 pounds to the cycle, but i bet strength would increase a lot too...