We use Mailgun at work, and I can attest to its consistency and performance in inbound mail processing. Our webhook is consistently hit within about 1 second when I send a test email to our app's email.
I will say that Mailgun's UI could use a little bit of help. There are a number of things that make it feel half baked, but in terms of functionality, as aforementioned, it's not lacking.
We were, hitherto, considering the possibility of using Mandrill for outbound mail, only because they seemed to offer more spam folder avoidance knowledge and analytical data, while Mailgun was (and is) surely preferable for inbound... that switch will never happen now.
Great feedback. Our UI is definitely something that could use some attention and is a big priority for us this year. We've made some big hires that are 100% focused on making it a great experience.
If you'd like to talk about more specifics, please reach out at anytime josh [at] mailgun [dot] com.
Another vote for Mailgun. I use them for all my side projects, monitoring, error reports, basically everything gets hooked into my FastMail account with all the right aliases I need, and it works very well.
I've never gone over my free allocation even when I have a dozen or so side projects up and testing.
Wow. Thank you guys for the suggestion. I really like that the first thing I see on the Mailgun landing page is sample code for calling the API, and the second thing I see is a pricing calculator.