Well, try what I said about mirroring, merging and then moving the mirrored half in your UV coordinates, then rebake. I'm willing to bet that fixes your problem.
Nope, it's every scene I open, and even new ones. It struggles with a mere cube. Sickening. And video drivers I havn't touched... perhaps I ought to update.
Orgoth, you're astute and impecable verbal prowess is unmatched by any mere mortal man. Anyway, added some swirls in the diffuse, it helps it out significantly i feel.
Doom 3 isn't meant to be run in Ultra mode, that merely disables texture compression completely and the official word is that it requires 512MB video RAM. Use high instead.
A bunch of verts along the middle seam aren't merged properly. Other than that I think the texture on the handle looks a bit flat. Try to work on that a bit more. The model itself look pretty neat.
One thing I ran into while working on the mesh was connecting pieces together and not having the edges line up. Are there any suggested methods for bringing edges together across pieces or collapsing edges when merging?
It looks like there is a line that runs down the middle of the rail that could be removed. There is also some kind of ring on the front which I'm assuming is for the strap. That could probably made floating instead of merged with the main body.
Good post Ninjas :) You give some good insights into what it takes to be an indie developer. You ought to get it merged with that other thread so it doesn't get buried, or maybe just re-post it in there.
I found info in this thread and @Jerc mentions that this will be addressed in the next hotfix. https://polycount.com/discussion/137389/substance-painter-latest-build-2018-2/p6 Hopefully this helps anyone else that runs into this issue.