This will be my last, comprehensive post regarding the topic. Refer to it for anything I have to say regarding this match-up; I'm done with bickering on an individual level.
1. I am not saying any fighter can surely win - please understand this. It only seems I am on Kakashi's side because I am mostly defending against fallacious arguments presented on Minato's behalf. I said it was a toss-up, and focusing on the idea that Minato outspeeding 8th grade Obito's Kamui does not provide definitive proof it could do the same to Kakashi's, which outsped 30 year old Obito's Kamui.
2. Minato admitted Obito's Kamui at age 14 pushed his Hiraishin to the limit; it came down to a split second, and Minato edged out. Minato also admitted that Kamui was better than Hiraishin. The reason Hiraishin ultimately prevailed in that scenario could very possibly be attributable with the fact that it was in the hands of an inexperienced fighter. In the hands of a more experienced fighter, what Minato said may possibly (not certainly) hold true. Kakashi's Kamui outsped the more experienced version of that 14 year old Obito's Kamui - the one Minato admitted pushed his Hiraishin to the limit, and admitted was a superior jutsu overall to his Hiraishin and Tobirama's.
3. The ability to react to Juubi Madara bum-rushing him combined with his ability to interrupt teleportating summons indicate the speed at which Kakashi could execute his Kamui is within the ballpark of Hiraishin. It is not superior, but should be comparable.
4. Kakashi's bad vision only was mentioned in his very last Kamui usage. If we are going to handicap Kakashi to the version he was in after two days and used god-knows-how-many Kamui, then do the same to all battledome characters. Minato's last moments alive were impaled on a claw with no chakra left. Jiraiya's last moment alive was impaled by half a dozen black rods and missing an arm. Itachi's last moments alive were spent blind and barely able to move.
That is literally all I have to say on the topic, and any quote I would hypothetically reply to someone with would only be a permutation of the above. Quote wars have no end and even when proved wrong, nobody will change their opinion due to the cyber high horse they are on, and I don't intend on turning this into a battle of attrition to see who has more spare time on their hands.