After reading everything I could get my hands on here, and now using my 510 for about a month, I've come to the conclusion that there is no way to predict the life span of an atomizer.
I'm still using my originals, plus a couple of the back-ups I ordered. I now consider them "disposable" - if one dies, I'll always make sure I have plenty of back-ups to rely on.
The cost of an atomizer is minimal, especially when I compare it to the cost of a pack of cigarettes. $8.00+ for a pack of cigs - and checking around for reputable suppliers I see atomizers selling for less than the cost of one pack of smokes - so...
That said - I've found that by not letting my atomizers run dry (keeping my cartridges topped off with e-
juice), blowing them out gently if I happen to flood it (flooding happens, it's nothing to worry about) and not "fussing" too much with them , I'm getting good performance and life out of them.
As far as doing anything to make them last when you first receive it - see above.
Gently blow the primer fluid out of the atty before using it - don't run it "dry" (aside from not being good for the atty, it tastes awful) - and just enjoy
vaping!
Good Luck!