In a Man United forum its difficult to be objective about a direct rival especially considering how intense the prestige fight was, with Arsenal almost toying with the league with their swashbuckling way of playing - a very French way if I might say so.
The swagger and flair that they had in abundance, and also the steel in that team. They could be gritty which shows up in the number of draws that season.
To be honest a teenage me had my Keegan "I'd love it" moment when we beat them and ended that run, I absolutely hated the guts of that team. They dared to challenge us! United! And I'll forever begrudge them of that Invincibles badge. But yeah, even though their peak wasn't as long as it could've been, they were good. They were very very good.
Now two decades older I could watch Leverkusen in a calm and disassociated way, egging them on and laughing in disbelief as they came back late each time from almost certain defeat to somehow, yet again, fight to live another day.
From Neverkusen to Neverlusen, it was a joy to watch how they schooled the big boys of the league and also in the Europa. Its a shame that they didn't turn up in the final. I also really admire Xabi Alonso, even when he was in Liverpool seemed like a class bloke. A fairytale for someone breaking the Bayern strangehold on the BuLi, and in what underdog style!
So, after waffling on for several paragraphs, I think for me Leverkusen just edges it, but only just.