I ran AKG480's (mostly 483's) for a little over 2 years, and I made hundreds of tapes with them. This year I got Schoeps, and I've made probably 50 tapes with them. I still own a pair of AKG460's, only with CK8's at the moment.
The AKG 460's and 480's have that "AKG sizzle". Whether that's good or bad is a matter of opinion. I will give the 483's a lot of credit in that when you are in a bad boomy place, they will cut through the mud and come back with a "decent" tape when most of my other mics wouldn't. But that sizzle is fatiguing to me. I don't know if I've ever sat down with a pair of headphones and listened to a whole show I made with my 480's... after a few songs I get itchy to do something else. I'm not sure the sizzle "fixes" the boominess, so much as it covers it up by force. If you put too much salt on your mashed potatoes, you can throw a bunch of pepper on there, and soon you can't taste the salt any more, all you taste is pepper. Whether the overwhelming pepper is better than the overwhelming salt... that's a matter of personal opinion.
I've never gotten a muddy tape with my Schoeps, at least not thus far. The Schoeps are "accurate"... and if the sound sucks in the room, you will hear that on your tape. The AKG's are perhaps more forgiving of that.
For me it all comes down to this next statement, which is probably not going to make sense to a lot of people... to me the AKG's scream like a little kid "Look at me! Listen how awesome I sound!!", and they do sound awesome, but after a while I get tired of that screaming kid. The Schoeps are like a calm voice saying "don't listen to the mics... listen to the music..." and I actually can relax and listen to he music. No hype, no fatigue, enjoy the music.
What have continued to blow me away in the time that I've owned them are the Gefell hypers. No overwhelming sizzle, great smoothness. To me they sound "as good" as any other hypers I've used. I like that fact that I have whole mics with caps and bodies for the same price as Schoeps caps, that allows me to run on 2 festival stages.
I definitely don't think anyone can make a blanket statement like "Gefells are better than AKG's, and Schoeps are better than Gefells". Some nights this mic will sound better than that mic, another night it's the other way around. And what you like this year, will probably change to something else you like better next year.