I imagine both would work. Being FT, however, it would be sensible to post your complaint/comment on here and the issue it surrounds so we could advise you on how to best deal with it.

I continue to be amazed by how many people, including my Father, who insist on contacting AJ on any service issue they may have. There's a customer care process in place, and all my dealings I have generally been satisfied with the result.