In a slightly similar situation as you are, I think, holding a MPhil offer for SASP and a MLitt offer for KCL. Maybe sent me a PM for SASP, I've got friends studying there right now?
As far as I've been told, getting into the SASP PhD with a good 2.1 in any respectable philosophy master is easy. What is hard is getting funding - and that shouldn't be too different for other universities either I think.