Sorry for the triple post but i think i might be on to something. I dont think the attys break in. I really think it has to do with the battery. I was reading further and as i was puffing i noticed that when i got the best vapor i had screwed the bat in, unscrewed and screwed back in again and it felt like my atty was brand new! lots of vapor great throat hit! i think that some attys connectors need to be pushed up. The tighter i screw in the hotter my atty gets. i think some peoples isnt getting the full 3.7v outta there batt due to sloppy connection. Try pushing your atty up to connect better to batt and take short puffs (one after the other) to heat it up. Then see how it hits. For more info refer to the thread in this forum m401 atomizer trick.

Maybe this is it i dont know? Im still kinda new so let me know what you think?