Hi jroc,
23andMe provide only the raw SNP data, and as you say ancestral paternal and maternal (mitochondrial) DNA typing.
As you would know, you have to pay an additional $5 to run the data through Promethease. You retain access to Promethease's results for 45 days only.
There is some value in rerunning your results through Promethease a year or 2 down the track as the information attached to each SNP might in the future change depending on scientific advances.
I'm still confused about the DHFRP2 gene SNP on Chromosome 6 which like you gives a 4.6X increased risk of AS for me - I still think that this is probably due to linkage disequilibrium with HLA-B27 ?
Regards David