I just completed my first semester (evening) at Southwestern. My good friend and co-worker just completed his first semester (evening) at Loyola. Needless to say, we frequently took the time to compare our experiences throughout the semester in some detail.
Our comparisons strongly indicated that the schools are roughly equivalent in terms of the quality of the legal education offered. Interestingly however, Southwestern seemed to have a greater workload, as evidenced by the number of actual class hours (1-2 more per week), the length of the semester (about 1 week longer), and the greater number of graded writing assignments. In fact, my co-worker frequently commented, "You guys are really getting your money's worth."
With that said, had I been initially accepted at Loyola, I would have ended up going there. Loyola's ranking relative to Southwestern's would have been the sole reason for that choice.
However, your case differs from mine in that I wasn't offered a [full?] scholarship to Southwestern. So it really boils down to whether the actual difference in reputation between the two schools is worth an extra $100k over the next four years.
Prior to my experience at Southwestern, I would have struggled with the same question if I were in your shoes. However, in retrospect, there would be no struggle. I would pocket the $100k and go with Southwestern, easily. If it was a difference between Southwestern and Harvard, or even UCLA, I might be inclined to spend the extra $100k.
By the way, if you need a little more convincing, check out the library and newly completed courtroom at Southwestern in the Bullocks Wilshire Building. The new courtroom is beautiful, and is one of the most state-of-the-art in existence. It's enough to make you want to be a lawyer.
Good luck! You can't go wrong with either choice.