Never did any modules in the anthropology department while I was there, but in general my experience was that the lecturers are very good and really engaged in their subject and in teaching others about it, but the admin side was really, really poor. I mean in general uni admin is always a bit rubbish but SOAS has managed to probably managed to be the worst of the unis I've been at for the general admin side of things. However most students probably won't run into too many major admin issues (my particular situation meant I had to engage with that side of stuff a lot more and had to deal with the fallout of it not working much more).
Also as a bonus, they offer a huge range of quite uncommon languages, many unique to SOAS. If you are interested in the anthropology of a particular region and may want to continue to graduate work, it's an excellent way to get started on language skills in preparation for fieldwork later!