If conversation is all that concerns you then you can try Lily Hart. She's American and provides a reliably good GFE. Her services are pretty vanilla but she'll do athletic sex and a bit of filth (toys up the arse, etc). Besides Lily, my limited experience with British girls leaves a lot to be desired. I've not had a satisfying experience with one yet. When there's so many excellent Polish girls out there who speak good English I'm not too fussed about "buying British" anyway.