There are a lot of things to like about Elastic E-mail.
Very affordable. You get 150,000 e-mails a month for free. We currently send 300,000+ e-mails a month, and it only comes out to around $100. We're growing quickly, so the flexibility of their pricing helps. Interface is very simple and easy to use. When it's working properly, it's working great! Customer service is fairly responsive. I think they are heading in the right direction.
As far as I know, with larger companies like SendGrid, they sometimes completely ignore issues and will let bugs fester in your system. I haven't had this issue with Elastic E-mail, so I've stuck with them. I also haven't used any other e-mail platform, so I honestly don't know if everyone runs into problems like the ones I have in the past, so I'm kind of at a crossroads where I don't know if I should ride it out, or look to switch.
Mainly three things:
1. For the past year they have been going through many updates. Several times during this process, our e-mails just stopped sending, and we weren't alerted about it until I noticed the drop. For this past month, their graphs have not been working and I've been unable to track our open rates. As a result, we had to freeze our marketing budget and wait for them to fix it. It's been more than a month, but no progress so far. I have been told the problem has been resolved several times, and then when I went back to check, there was no difference. I've pretty much just been going around in circles with this problem.
2. Customer service is decent, but with notable limitations. First, only a few of their employees are truly responsive (Joshua, Andrzej, Beverly are all amazing!). Rest will try and give you canned responses for hours and hours, or they won't read your query at all and answer a completely unrelated question. I had to go back and forth for weeks sometimes until someone finally admitted there was an issue with something. I recommend specifically asking for certain representatives when you run into trouble. You'll know pretty quickly which ones are good. And second, it's not really 24/7 or as fast as they make it out to be. They respond "within the hour" but it's only with "Thanks for your e-mail, we're looking into this." Usually takes 1-2 days for small issues, and sometimes a week or more for bigger ones to be resolved.
3. We've run into a lot of problems as we've gotten bigger. We started on Elastic e-mail sending only ~5,000 e-mails a month. Now we're sending 300,000+ and there's a lot of issues with our logs being read incorrectly, throttling, deliverability problems, etc. We're considering switching to Mailgun as we scale even faster going forward, but still uncertain about it. Other startups that I know usually just set their e-mail systems and don't have to worry about it. I've had to pour in hours and hours into Elastic E-mail, trouble shooting through logs, making screenshots for their customer service team, etc.
I'm hoping the issues get resolved eventually, I'll come back here and update the review if it does. Until then, I'd say Elastic E-mail is a 3/5. Overall, I am fairly happy with them. I will say - by far the most annoying thing they sometimes do is pretend there is no issue when there is, and you have to go a very far length until they admit it and try and fix something. This isn't just prevalent on their support side, they even do it on review forums, where they try and disregard what previous customers have pointed out. It's EXTREMELY frustrating with companies do this. It's like when Comcast tells you "no, no, your cable is working fine," and you have to video yourself trying to turn your TV on to prove otherwise.
If you expect the number of e-mails that you send out to grow quickly, DON'T put too much weight on cost. Yes, when we started out, EE seemed like the best way to go because something like Mailgun was so much more expensive, but once you scale, the cost ends up being a small fraction of your revenue anyway, and you'll wish you went with your best option instead of the most affordable one.