[mmcdan]

For something as critical as email, "fine until Apple changes anything" is not good enough, given that Apple has a habit of changing things.

[andybak]

Yes but worst case scenario is you are forced to switch to a different client not that you lose any data. So actually not that critical.

[yen223]

"given that Apple has a habit of changing things."

Apple doesn't have a habit of changing things. If anything, I feel that Apple is too conservative when it comes to making changes.

[fallenhitokiri]

If Sparrow would be your only option to access your mails this would be true.