I agree. I think it depends on the circumstances, such as how much Itachi really knows about Pain's abilities, and how weakened by disease Itachi is (also because his eyesight was pretty bad by then). Either way I think at the very least, Itachi could take out at least half the Paths. I mean the Rinnegan is the most powerful of all the ocular doujutsu, and fighting multiple Paths at once is a challenege even if you know their secrets...but let's face it. Itachi is a freakin' genius, very skilled, very smart, and good with strategies. There's also the fact that he was apparently too stubborn to be killed by anything but his brother's hand.