Imagine Naruto's face when he would hit someone with his Uzumaki Naruto rendan only to have him standing back up and say in a Luffy-like manner "That surprised me"
![biggrin.gif](http://www.narusaku.com/style_emoticons/default/biggrin.gif)
Or if he stretched his arm. Thinking a bit about the reaction of Sakura when she got hit by the genjutsu of Kakashi during their first bell test.
Ofcourse if that person got hit with FRS he would be in trouble, think the rasengan only does heavy bludgoing damage right?