You will probably meet both types of fans. I did this in 2011 and some people around me were cool and we joked around, others were vulgar and idiots. We got stuff thrown at as throughout the whole game including snowballs, drinks, and even beer (cue yewt disbelief). It was definitely an experience though. You'll probably find more disgust and lack of desire to return to Eccles because of their behavior but will love having the experience. It might not be as intense now as it was then because that was the final game of in conference match ups between the two when I went