To get a meaningful response, you probably need to tell us what you plan on using the software for and where you are located? When I last looked at DIgSILENT, it did not have many ANSI/NEMA devices in its library. But that's been a few years ago.
Never used it, never seen it, never met anybody that did. Maybe, then, it's the "best" in a very niche market... Probably the "best" is whatever most of your neighbors are also using. In my case that means that ASPEN OneLiner is the best. There's a few outliers that use CAPE, but otherwise it's all OneLiner. That's thousands of square miles and many GW of load.
"Better" and "best" are obviously very narrowly defined and there's no portable answer.
I’ll see your silver lining and raise you two black clouds. - Protection Operations
I have used both ETAP and PowerFactory in a previous role (using CAPE now in my present role). ETAP seems more tailored/focussed on industrial power systems while PowerFactory seems to be used more for transmission power system modelling. As a result, the component models / libraries of each software package are more suited to their respective strengths / areas of focus but can also work perfectly fine for other modelling scenarios. Both softwares have multiple extra modules that can be added for extra functionality / power system study types (at a price!). PowerFactory also has an EMT module which (as far as I know) ETAP does not. I find ETAP to be slightly more user-friendly for beginners but PowerFactory to be more powerful / flexible overall. Comparing like-for-like I think ETAP may be slightly cheaper (depending on what modules you need).
But as other posters have said, which is “better” for you is always going to vary depending on your intended use for the software (project types / use-cases), budget, customer or internal company requirements, etc.).
