Malbecs from Patagonia are quite different to Malbecs from Mendoza and Salta. Not sure I agree with the Cahors comparison but thats another thread material.

In general terms, Malbecs from the south will be (in general) less powerful, have more minerality and acidity as their counterparts from the north of Argentina. Its a very interesting experience to try three malbecs from Patagonia, Mendoza and Salta... this can be an eye opener...