Digital Cable from Transport to Dac

I'm using a Proceed transport MkIII and a Proceed D/A MkIII with a balanced Transparent Audio interlink between them. My question to you Audiophiles is what method of inter-connect sounds best and why? Given the fact that both of my units have all 4 connection types, what experiences have you all had in listening to the other 3 types of inter-connect ???? I am open minded to any suggestions and willing to buy someones cable if they are selling one with good intentions. Input is really appreciated. Krellpower1