Dapol and Hornby couplings .....

Yes.

That will work fine. "Tension lock" is the generic term for the hook and bar type couplings used by Hornby, Bachmann and Dapol. NEM pockets are a type of fitting that allows the couplers themselves to be easily detatched and replaced by a different type, should you so desire (or, for that matter, replaced by spares if they get broken). Hornby themselves are now moving towards using NEM pockets on their models so that the couplings can easily be changed or replaced.

One of the advantages of NEM pockets is that spares from any manufacturer will fit models made by others using the same fitting. For example, this pack of spare couplers from Hornby will fit any model that uses NEP pockets to attach them:

Thank's for the detailed reply Mark :-)

Chris