Seriously, WHY BOTHER?
Sure, there is an immense ego-boost attached to this. Few would dispute that.
Yet, when you come to think about it, str8 dudes really do not go around messing with other guys. That's why they are called str8 and not gay or bi-curious or anything else. So, the ego-boost is more of an imaginative gain than anything else.
I have tried few times, obviously having too much time at my hands and being curious to a fault. I did score a grand total of two hot dudes over the years, who apparently had been str8 before and for all I knew, returned to that state afterwards.
Frankly, all of it was much ado about nothing. Sex was pretty mediocre. Definitely, not worth the effort I had put into landing a str8 dude. But, hey, I sure tried.
Besides, if it is only for an ONS, who would wish to put all the time and energy needed into something you can easily get almost anywhere? If you see a 'further prospective' like in a fuck buddy, you are facing two old questions:
How straight is straight, if it is more than a one time experiment?
Do you really want to be on the sidelines of his respectable 'hetero-life'? Or do you want to have your fair share of fun, too?
Just some food for thought, I guess...
KD