whats the benefit of Amazon SES, Mandrill, etc.



I am wondering if anyone can share their practical experience with the paid email delivery services. What exactly is the benefit of it?

I have a dedicated server and have been sending out our newsletters for years to about 250,000 subscribers and I have never had any problem with delivering the emails using the servers own mail system.

Why should I pay a large amount of money (in our case it would be around $1,000 a month) to use one of the paid email systems. What improvements would I get? Do open rates improve and why?
@Vroom - I think the point is that not everybody is technically inclined to setup and manage an email server and that's where these providers win.
I wanted to test this out, so I signed up for Amazon SES today (its the only one that is relatively cheap). I sent out 20,000 emails as a test, and it went out lightning fast. 3 minutes I think, and they were actually delivered in the people's inbox in 3 minutes, because I was getting opens immediately.

I will give some feedback tomorrow about the open percentage compared to sending through our own server. Because that stat is what can justify spending money or not. But it feels really nice to instantly see the bounce count and complaint count. You know exactly where your list stands. You don't have to worry about miss-diagnosed bounce emails, etc.

Another great thing, no server load. Usually my server load will be up around 6 to 8 when its trying to send 250,000 emails. And it takes it a few hours. But with amazon SES, they do all the work. So my server has no load and is ready for visitors.
Did a couple test mailouts through Amazon SES to hotmail and gmail. What I found is with gmail the email went to the promotions tab, and results were the same as if I had sent it out with my own server, so it was a waste of money for that.

With hotmail it was different. The open rate was higher than if I had sent it out from my server, suggesting that the messages were going to spam folder when I sent it myself.

I will test yahoo tomorrow. In the end I will probably keep using it for hotmail and some of the harder to deliver to domains. The best part is that you get instant and accurate bounce results so your lists are "clean" after just a single mailing.

Google seems a lot more fair and transparent when dealing with the small time mailers. For example out of 70,000 emails I sent only one bounce was found, because gmail was always replying openly with bounce messages and never blocking my server in the past - and always delivering the messages.

With hotmail out of 20,000 messages it found 500 bounces (2.5%), because hotmail was often doing things that disrupted mailings and made bounce messages unreliable (temporary blocks, etc.).
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Vroom: I've also found Amazon SES to be reliable, screaming fast, and stupidly cheap. Since we're able to associate as many domains with our SES account as we like, it's massively scalable. What was the result of your test with Yahoo?
Yahoo was same like our regular mail server.

The random small domains also performed well like hotmail. So my final conclusion (I will still test a bit more), is I will use my own mail server for gmail and yahoo (which make up 80% of our lists), and Amazon SES for hotmail and the random domains.

I would like to do a small test on mailgun still to see if there is any difference, but I suspect all services are basically identical.
Hi When I tried to use Amazon SES> It is giving me this Error upon Validating.

Any ideas how to fix this? or if I am doing something wrong.

  • The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details.
    The Canonical String for this request should have been
    The String-to-Sign should have been
I got the same error the first time I used it. I made another smtp user and added the privileges to it as shown in the video tutorial, and then I created the API access information and paste it into mailwizz. Then it worked fine.