Hi Mike,
Hella had discontinued the harness and it was out of stock, so no, the harness is not available.
As to the ST170 vs halogen Dynabeams, The projectors in the Dynabeam headlights will provide a more focused beam as compared to the reflector set up with the ST170. As well, the free form high beam of the Dynabeam is exponentially brighter than the ST170. Both require the VW harness conversion.
Obviously there are cosmetic as well as mechanical differences with the swivel movement of the Dynambeam low beam projectors.
Any questions/other, please let me know,
Thank you,
Chalon