Sometimes i fake it, like for men who are so old, ugly, fat, even if theres a slight scent of his under-arm BO it turns me off big time.
Other than that, i usually orgasm quite easily from fast/hard sex, especially if theyre good looking, plus i find that sex with strangers really gets me going, id never tell my family or friends that.
Regarding oral, i love it both ways. Ive been in a gangbang with around 20 men of all ages and sizes. Sounds like the details of that would sound too gory for some people here though.