I've only just started using this as a GM, although I have been a player in a campaign where the GM uses it for a while now.
I like it. I found it pretty easy to learn and use, although better documentation would be nice. The YouTube videos are helpful, but not really comprehensive enough.
Keeping track of all the things going on in a RoleMaster combat can involve a lot of bookkeeping, and this program does an excellent job of that, and this is especially helpful in a large combat - the last one being 5 PCs and 8 monsters - it made the combat flow a lot more smoothly.
[4 of 5 Stars!]