Wouldn't it be more appropriate to ask the women?
Each woman is different and turned on by different things and some can come just at the build up even before you touch them so there is no single answer
I have very little difficulty bringing women to orgasm through oral sex, including many who claimed to be non-orgasmic. Following orgasm(s) from oral sex, it is considerably easier to bring them off during vaginal (or even anal) sex. Without the oral sex, I can't claim any more than 50% success with straight vaginal sex.
That being said, the points made by jeff970 and blackpoolguy are both valid