User blog comment:Joji200/Feitan vs Hisoka/@comment-14902757-20150826061514/@comment-24287488-20150826071631

About 5th one, I'm not so sure about that. IIRC Tsubone with Amane was able to catch-up to him when he was escaping with Alluka. So I don't think he's that fast. And during Feitan's battle with Zazan, he wasn't even in his top speed. Who knows how faster he can be... and just like you said in one of the para, Feitan isn't stupid either and is far more experienced than Killua. What if he guards himself with Ken against Killua?

Then I suppose the result would ultimately depends on the circumstances of the battle. Killua's ability is only and ONLY effective when he is to make a surprise attack on his opponent. If they were (for example) fighting in Heaven's Arena, where there are chances that both know each other's abilities, then I see Killua easily losing it.