Rebound is 2.4 times stronger on a mg/mg basis absorbed (ki .18 for ATD vs ki .43 for 6-OXO). Also, Rebound may be more bioavailable. Thus, Rebound is probably going to elicit a stronger t response based on an equivalent dosage.
Stacking Nolva and any anti-aramotase is not recomended. Author recently hinted that competitive binding at the hypothalamous may be counterproductive when they are stacked. That said, a low dose of 6-OXO may be beneficial in that it could futher increase t without supressing estrogen.