The best bootlegs from Unf. Fire IMO are:
10-23-84 Nantes France (soundboard, complete) * there is a lesser quality incomplete version floating around also.
11-21-84 Dortmund Germay (FM broadcast) 10 songs total, (13 were played that night) so it is imcomplete, but it sounds excellent.
3-21-85 Chicago is one of the better audience recordings from the tour though. I would also suggest the audience recording of 2-5-85 Bologna Italy. Very similiar to 3-21-85 as far as quality.
Hope that helps.