Better Argentine Malbecs – worth the money?

See also Julia’s tasting notes on more than 50 premium Argentine Malbecs.
 
In How good are Argentine wines today?, Jancis reported enthusiastically after judging at the first ever Wines of Argentina awards. At that time, Argentina was continuing to do well in the US but sales were falling in the UK.
 
However, Wines of Argentina UK recently announced (with almost audible whoops of delight) an increase in exports to the UK for the third consecutive month and an upward trend in value (up 17.4% to $37.7 m), volume (up 1.9% to 1.8 m 9-litre cases) and average...