where your gaining with stage 2 is because of the down pipe and decat/sport cat.
the map is no different in terms of fuelling, just stops the warning light as i said earlier.
i was thinking about going stage 2 when i bought my milltek and jkm and superchips told me to save my money and keep the stage 1 map if i didn't mind a warning light every now and again as they're more or less the same