I switched back to Airmail on OS X last week as it was pretty obvious Mailbox was dead as there were 2 critical bugs regarding switch and images not loading that hadn't been fixed in months. It's a shame but that's life.
I have to manually setup the rules/filters for now but reading through some other clients in the app store they seem to be buggy. I used Airmail years ago before Mailbox and it was stable and has been since switching back.
I thought it would be at the $9.99 price point, like Sparrow was. I am surprised by it being $20, but I understand given the limitations and will purchase it.
What happens to the tokens when people pirate this app? Does it count towards their limit?
I really like Foundation based on the same points you raised.
It does support IE8, minus the responsive stuff, it's < IE8 that it doesn't (http://foundation.zurb.com/docs/support.php), and that's a deal breaker for me and why I've never used it since most of the sites I build still get around 10-12% from IE7.
You could use the older version of Foundation, but that doesn't appeal to me either.
In iTunes, when you're in the iTunes store, click on your email address in the top right corner to go into your account. Click the 'see all' for 'Purchase History' and then report a problem. If it's the last app you bought, click the button for it and then a link will display beside the price which you can click and fill out a form to ask for a refund.
I have to manually setup the rules/filters for now but reading through some other clients in the app store they seem to be buggy. I used Airmail years ago before Mailbox and it was stable and has been since switching back.