I did Asnac for very short space of time, and would like to advise you to think very carefully before applying for it. The claim that they teach the languages from scratch I found to be somewhat suspicious. Their idea of 'teaching' the languages consisted of getting 30 people together in a room, making sure everyone knew what an inflected language was in the first 5 minutes, going round the class and getting everyone to read a line of Old Norse from a passage (in the first lesson!) and then giving you a passage from an original text to translate for homework with no other help than a vocab list. The guy who took the first Old English class basically expected us to be able to teach ourselves, and the Medieval Welsh tutor was actively trying to get people to quit his class because too many people wanted to take the subject that year (which was the Department's fault for admitting too many students). No proper grammar teaching, no chance to build up vocab gradually. Be very careful. I would strongly advise you against Asnac unless you are already doing something like Latin or Greek A level, which makes it vital to know points of syntax and how inflected languages work, or are a natural whizz at language learning.
With regards to the general atmsophere of the subject, I found it to be a cipher in the English Faculty. It had 2 or 3 rows of shelves in the English library and appeared to be a homeless subject - we had lectures in the History Faculty, Law Faculty, Economics Faculty and Raised Faculty Building all in the space of a week. I disliked being shunted round from one Faculty to another, as such a thing didn't exactly help me feel settled. We also had people sitting on the floor in quite a few lectures, as in that year the Department had let in too many first years. Hopefully they've acquired a bit more commonsense since last year...