6 months ago they had lots of construction going on in the non-secure area of LIM (extending the second floor over the ticketing area or something) - and trying to overnight there was almost unbearable with the banging and noise... especially since there isn't much to do before checking in and getting through security.
After security, I couldn't tell you - I don't fly through there enough. But my advice is to stay in the secure area.
(BTW - does anyone know if the construction is finally done, and if so, what they were building?)