I rate Kakashi and Gai on the same level without kamui. Manga always implied that they were equal since part1 and Kakashi gained kamui during the skip-time. But i still actually rated them equal before until Kakashi's recent mastery over kamui. So normally, the fight would be tough but with a Kakashi winning high difficulty.
I know people will mention gates, but Kishimoto tried to create a parallel between 6gated Gai and Kakashi(using Raikiri) to show us that Kakashi can actually
You must be registered for see links
with or at the very least that they were rated equally. Actually, recently Gai admitted that Kakashi
You must be registered for see links
. Furthermore, Kakashi is more versatile than Gai IMO. A combinaison of doton hiding mole+raiton kage bunshin can already put Gai in trouble since if he hits the clone, he gets paralysed. Genjutsu is no option though since Gai trained to avoid it, but other ninjutsu versatility(suiton, raiton, etc) would make Gai struggle.
I also actually rate Neji as superior to Lee. Neji is as fast if not faster than Lee in base, and his rotation gives him a great defense against Lee in gatesm adding his vaccum gives him a good range attack. So at the end, i see Kakashi and Neji winning probably with high difficulty
