I have a problem with my maps. Basically my mesh is looking different in marmoset toolbag from substance painter. I dont know why, i worked in PBR spec gloss in substance and every map is plugged in correct in marmoset. 1) My specular map of a bullet 2) How it looks in Marmoset 3) How it looks in Substance
Probably Metalness / roughness might work instead of spec / gloss. If you want to, change the camera settings to post/effects/tonemapping/ACES. I find that gets close to substance at least for me and my lighting <when i setup the lighting to mimic substance.