I've been to all B1G stadiums to see a game except Nebby, although I have walked into the stadium to look around. My two cents from my visits :
13a--Rutgers (once). Nobody knew anything about Iowa. Seemed weird to be playing 30 mins from NYC. Small and quiet crowd when I was there. Not easy to get to. NJ sucks in general. No parking. Little public transportation. They need to be back in an eastern conference. We paid way below face to sit on the 45 on the home side.
13b--MD (once). Easy to get to off the beltway. A FB program stuck on a BB campus. Little excitement when I was there. People attended as an outing. They really need to be back in some eastern conference.
11--Illinois (lost count....8?). Only because I will travel to watch the Hawks play there. The visitor side of the stadium was not renovated...bathrooms suck, there's a wind tunnel inside the inner circle. There are restricted vision seats. Fireworks were cool but annoying. Students do seem to have the choreography down. No real vendors around. You can smell the cow dung with even the slightest of south breeze. Awful stadium in an awful town.
10--Ross-Ade (three times). Ugh. Another nondescript stadium in a dumpy town. The bass drum and locomotive were OK, but annoying. Downtown isn't far away. My first time was the 85 tilt with Long and Everett...fun down to the wire. But the last two times were ho-hum, and the stadium needs repairs. The inner circle feels like you're in a dungeon...dark and dank.
9--MSU (once). I was at the 09 game. Loud, yes. Full, yes. But damn, it's a long ways from anywhere. Zero around it. And the stadium is rather sterile with little tailgating next to it. I got like zero vibes regarding the structure itself. Probably won't ever go back there again.
8--Indiana (four times). May be ranked too high here. Dead environment with constant "and that's a Hoosier FIRST DOWN."...zero people there to watch the warm ups. And they added 5000 seats when they were half full to begin with. Another FB program in a BB town. Brown county is beautiful and the stadium is easy to get to, and yes, park right up next to. You can leave at half time to get your drink on and return to your seat. Excellent campus.
7--Penn State (once). Not really impressed. Seriously. Been dis-jointly renovated so much it looks like a tinker-toy build. Decidedly difficult to get to, and parking is a mess. No real bars or food joints around within walking distance. They play that obnoxious cat scream constantly.
6--Ryan Field (lost count...10?). Actually a fave place of mine. People give it crappy reviews but it's been my Kinnick away from home. Easy to get to off the Metra. Lots of energy due to Iowa fans filling it up. Mustard's Last Stand is a must-eat location. Some decent bars within walking distance. Not a bad seat in the house.
5--Michigan (once). 1st class operation all the way. Golf carts running all day to assist people. We had our own section usher. Clean, and yep, big. Not all that loud as you know, but big. Can't argue against 110K people in one location. They can even cheer twice when both MSU and OSU lose. Not a lot of bars, etc near it that I recall. Fun but not exhilarating
4--Minnesota (twice) I'll give them props. Excellent stadium and they sell beer! Park at the fair grounds and it's a breeze getting there. They can move people with the best of them. Small but loud and very clean. The food venues around the stadium are pure minnesota-ian. I really have nothing bad to say about the venue, other than some fans.
1c--Madison. (four times). Party time! Stadium is within a block of downtown. Loads of fun, alcohol, energy, and noise. Inside rocks. Easy to get to if you ride the city buses. I've never seen Iowa lose there, so that's something.
1b--Ohio State (three times). Hard to argue against 108K extremely hard core fans. Take a raucous Kinnick and add one-THIRD more people. You get the idea. Hiney-Gate was the BEST party I've ever been to. Period. A bit difficult to get to and it's steep in the upper deck, but it was quite the shrine.
1a--Kinnick (dozens). The only drawbacks are it's a bit difficult to park close to, and, there's no real nightlife close to it. Everything else is first class. Go Hawks.