Kakashi is very good, but jiraiya is way GOODER, this is an insult to the legendary sannin, the man that the the third hokage had always wanted to succeed him, and would have hadn't he spent years trying to bring back orochimaru
Jiraiya has more experience,sage mode and toads.
Kakashi has the elemental advantages, Jiraiya has no counter for kamui, but still hard to see Kakashi winning.Kakashi will surpasse him soon.
Are we talking about Kakashi with a now very well Kamui? Good enough to teleport away the arrows of Sasukes Susanoo? Don't forget that Jiraiya need time to get into his sagemode. This time Kakashi won't give him since he can use a very pronounced Kamui.
if j-man starts in the SM, easy battle.
if j-man starts in the base and gets to SM in the battle, mid difficulty.
if j-man doesn't use SM hard victory for J-man.