I will not know whether this sentence is correct based on GMAT rules, because I do not know what GMAT rules are. That aside, let us think of some idioms.
Rule 1. You use the idiom -as x as y
- in positive cases, where there is no negative word used.
E.g.; Gregory Peck was as tall as Rock Hudson
Bill Gates is as benevolent as Warren Buffet.
But in negative cases, mostly using a negative word, the template idiom will be - so x as y.
E.g.: Gregory Peck was not so tall as Rock Hudson
Bill Gates is not so benevolent as Warren Buffet.
Going by the above maxim, the correct sentence should be
REVIVING LG Electronics is not nearly so daunting a task as
reviving North Korea – the critical decider being the negative – not
The other point raised in the thread, whether the sentence should start with the task
as the subject or not is optional. That will be one more way of presenting your idea but not necessarily more grammatical than the text. As daunting a task as
is not only a legitimate usage but also a more literary one.
GMAT Club Premium Membership - big benefits and savings