Overall do I think he is the most EFFICIENT sensor, yes definitely. But like I said it depends on the mission. Since I don't think we are talking about pure Sensor-Type Ninja's (Naruto wouldn't be one of those such as a Karin), we can look at someone like Tobirama who put his finger to the ground and knew how many enemies were surrounding them, what village they were from and what squad:
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Like I stated above the problem is Naruto can't do it all when it comes to sensing. Can he do some of the more important things that other sensor-type ninja's can do, yes of course. But if he had to do what Karin did in finding Danzo, I don't think he could (If Naruto had never met Danzo I mean cause obviously then he could in SM and as for KM well I don't know if Danzo had malicious/evil intent, he was trying to do what was best for the Shinobo-world/Narutoverse as a whole in his own way and he was able to sense Kisame because Naruto had a "a vague feeling of malice." (As one should note Samehada's and Kisame's Chakra was the same in that state.):
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That last page obviously shows that even the best Sensor-Types wouldn't be able to sense him, so I definitely put Naruto up there as having top Sensory-Type skills but as for, the best, I am still not sold on it yet.