I am 90 % of the time M button OFF too. It is easier and more natural to manage throttle despite the fact that the lag seems more noticeable in default setting. I also noticed that overboost comes more predictable but then hits sharper in default mode which I like. In fact, what I would like to have is best possible response and least possible lag in non-M mode rather than the M mode. Exhaust mods helped already getting there and now I will add a filter plus a charge pipe and will probably stop there.
2011 BMW 1M: Euro spec, w/out Nav, manual seats. Evolve Race+N55 mid, Michelin PSS, ER charge pipe, aFe ProDryS drop-in filter, CDVx, BMW-IND trunk spoiler matt cf/VO stripe, BMW blacklines, BMW black grills, IND side gills&rear M logo, silver turn indicator bulbs, anthrazit overlays on side creases and on air curtains, MPerformance steering wheel w/VO ring, BMW steel pedals, custom mats, color matched MPower e-brake.