They both contain Arimistane so no I wouldnt stack the two. T-X3 is more of a general testosterone booster while AD3 is more of a PCT product with Prolactin control, Liver Support etc.
I would personally look into Alphamax if I were you. It contains the full 75mg Arimistane like both products mentioned but has a much more complete profile, providing full doses of Divanill, L-DOPA, 95% Forskolin, Vitamin D3 etc.