Is twelve moon upper demon moon 1 in a whole completely different level than the rest of the upper demon moons? Currently in the manga twelve moon upper demon moon 1 is ,


   Fighting 3 demon slayers hashiras at the same time, including the most powerful hashira , plus another demon slayer (4 demon slayers total)


and before, 


   Zenitsu (not officialy a hashira yet, though likely in hashira level) fought upper moon 6 and defeated him alone


Is twelve moon upper demon moon 1 in a whole completely different level than the rest of the upper demon moons, or is there any other upper moon which comes close to his level?
Upper Moon 1 Kokushibo is definitely strong in his Moon Breath Techniques but can't seems to use any Blood Demon Techniques. I have to say, Upper Moon 2 Doma is quite near his level since his summons can already deal with Hashira level Demon Slayers. Doma's weakness is his glutonny and his overconfidence since he always lets his enemy injure him.