Having been to most of the schools in the conference (in full gear, nonetheless - so I get the worst of it), here's my rankings, from worst to best:
Texas Tech - As a friend of mine said, "Every person here wants to have sex with us." I was called a f*g more times than I thought possible. Alums wouldn't even stand for fight song, everyone leaves early to hit the strip and get booze before end-of-sales at 9 since Lubbock is dry.
*Honorable mention: Toledo - would be right around here above Tech. First words a Toledo "fan" said to me: "I'm going to key your Honda." Everyone there is either an OSU fan or a Michigan fan. They're just too dumb to get into either school.
(BIG GAP)
Mizzou - Good tailgating. Fans were OK before the game, rather hostile afterwards (the tailgating may have something to do with it). Good amount of hell thrown our way, not near as much as TT or Toledo, but enough to get annoying.
Kansas - Football only. I think it's because they're not used to winning. Got a little grief, but not that much, mostly general ribbing. I imagine KU basketball fans would be much worse. I'd put them at "neutral" between good and bad.
Kansas St. - Experience was pretty good with the exception of my car getting trashed. Nothing serious, just rubbed off some of the window chalk and put some trash on it. Gets a boost over Mizzou for people offering us free beer after the game and being generally kind.
Oklahoma - Alumni were very nice. All the people around us tailgating were kind, giving us directions out of town, conversation, tips, etc. Got some crap heading into the stadium, but it was a pretty good experience.
The only two things I'd dock them for is some 5-year old running his mouth (he probably didn't know any better), and the following incident:
Flag Guy is around 10 feet in front of me on our way into the stadium. Drunk OU fan (a student) sees him and starts cussing him out, "F*** YOU CYCLONE!" and starts moving towards him to pick a fight. His buddy, grinning, all of a sudden notices that the Cyclone his friend is messing with (who's smaller than him) has some very big backup just behind him (yours truly) who's glaring a hole through his head. The grin goes into a look of "Oh, Shi.." and he grabs his friend and says, "No, man, it's cool. They're just supporting their school..." while glancing over at me. Fun times.
Nebraska - Very respectful to us. Nothing but general, harmless ribbing. Good conversation, very welcoming. Probably because the realization that they weren't going to be very good was dawning on them.
Texas - Far and away the best fans I've dealt with. Not ONE SINGLE negative thing said to me. Lot's of "Good luck", "Thanks for coming, good to see you here," and compliments on our outfits. This was the year after their national title (so I was expecting a lot of arrogance - which I didn't see). After the game, some of their fans even invited us to tailgate with them and tossed us their extra food (since we didn't have time beforehand), showing off their friend's NC ring. Great experience, really looking forward to going back to Austin.
TBD: Texas A&M, Colorado, Oklahoma St., Baylor
I expect CU to be around Tech, they're renowned for their horrible fans. A&M I'm not sure on, hopefully somewhere around Nebraska, but may be lower around Mizzou. OSU and Baylor I'll get back to you on after the season. If I had to put our fans somewhere, I'd put us on the upper end. Unless you're Iowa, you probably won't see much trouble out of us.