We gave it a shot but there were a couple things we needed that we couldn't get from DMS. Specifically, I have hourly jobs that started taking longer than an hour to run. I needed timing-based alerts for that. We also needed to be alerted in real time in a way DMS doesn't provide.
There are others, like Proby (which I mentioned here [1]), yet I find that having more competitors in that space would be helpful, because not everyone has exactly the same needs. Congrats for shipping!
