adding to this jumble of thoughts, ive hit both, i hit my uncles R flex, 10.5 degree HX, i hit it ok, but i hit my S flex, 9.5 deg hibore xl farther/have more controll.
i also hit my bosses 5900 sq, BUT it was an X flex 8 or 8.5 degree haha, so it was like swinging a 2x4 lol. but it hit decent for what it was, it also had much more feel than the calaway, and more workability/controll imo.
hope that helps ya, if i had to decide between them id get the nike, as it has more tech into it, and is an overall nicer club, the callaway is a lower end club, just above the big bertha i believe, the nike is top of the line, not that that means much, but jsut food for thought