Here is a decent (maybe slightly rambling) review of the software:
https://www.youtube.com/watch?v=PqWYT6Ikdww&t=187s
I have a lot of experience with the Dominator, all very positive. I went over the software myself and the look and feel is the same as other Holley software. There are definitely differences between the software but they are all directly tied into the differences in hardware between the Terminator X and the other ECUs.
Most guys that want to run a common crate engine don't need super advanced features of the Dominator. Besides, to take advantage of the Dominator advanced features, you really need a deep understanding of what you want to accomplish. The Dominator is really only necessary for (drag) racing applications.
Also, let's not forget that the Terminator X is for LS engines. There are hints in the software that Coyote and Gen3 Hemi applications are on the way. Older engine platforms are not supported.
Andrew