MIT Matrix 6 Balanced Interconnects

Do any of you have any experience or even information on the Matrix 6 line of MIT balanced interconnects? I can’t find any mention of them in their old catalogues (though I’m not sure when Matrix 6 cables were produced/sold). 

I have their interconnects AVt 2 interconnects which I’m told was their low-end offering. I’m trying to determine if the Matrix 6 would be a step up.

Thanks.