So I've been using the Substance toolkit for ~ 1 year, and my use has been plagued by performance issues - although really only with Painter. First off is the exorbitant amount of RAM it uses - it is probably the only program I have that sucks up nearly 6 Gigabytes of RAM for even small/medium models (<10,000 tris and 1024px textures), and I'm sure if I had more than 8 Gigs of RAM it'd use up much more, which suggests a memory leak issue. Closing the program also doesn't actually 'close' the program, and while the window is gone, it can take up to 2 minutes for all the memory to be released completely (might be an issue with the speed of my RAM).
The other thing, and this is for all the programs, is the frequent stuttering and freezes. I think it's something to do with how it communicates with the license server, but every 30 seconds or so the program will freeze up entirely for ~5 seconds, making it incredibly frustrating to work with. It seems to come and go in between computer reboots.
Lastly, is the fact that the viewport previews don't seem to represent the final result in UE4 or marmoset. Is that just how it is, or is there some graphics setting I've turned off accidentally.
I don't really know what this thread is for, kind of a rant, kind of a "anyone else get this problem?"