I'm only on a moderate dose of estrogen and anti andro, but defiantly notice there is a much larger cerebral side to my libido.
Stress, and and emotion never conquered my T driven sex drive, but now the odd though will deflate an erection, if I can get in the mood to want one.
However, if I am truly mentally turned on I maintain an erection, not quite the same pre HRT, but the orgasm is 100x more pleasurable because I can only attain it if I am truly, completely commited to having one, I now see the trouble women have with the O, it's all in your head!