I dropped the idea of using Postmark after I read this blog-post: http://blog.postmarkapp.com/post/1431120311/oddities-in-gmail-delivery-adaptive-filters http:/

I dropped the idea of using Postmark after I read this blog-post: http://blog.postmarkapp.com/post/1431120311/oddities-in-gmail-delivery-adaptive-filters http://blog.postmarkapp.com/post/1431120311/oddities-in-gmai... In there they admit that mails sent through Postmark still end up in Spam-folders or black holes. That was basically the only added value I'd get from using them.