Soju,

Yes, I am aware of check in at Row A..Very nice too..

However, there are two security check areas near gates "C" ( only speaking from my experience.)
One security check is on same level at THAI lounges, and the other is on same level as the shops.
In future, I will use the dark and gloomy security check on level 3, rather than the overcrowded one on the shopping level.

All the best from MEL...................Peter