Few subjective thoughts on the matter:
-@myclay, just use auto_export on change in SD and bind some reload textures macro to a hotkey (e.g for img in bpy.data.images: img.reload()*). It’s more streamlined than archiving substance and then going back to do changes, rearchiving etc.
-@Painter vs Blender paint. It’s bad comparison. In Painter you paint with materials, or masks unhiding complex multichannel materials. Suppose you could do that in Blender also by defining several Principled shaders and using AO/Curvature masks. I have a feeling we’ll get there with 2.8.
-@Film or Game only. Truthfully it takes A LOT of effort to create complex materials in SD. Also once a complex shading network is defined, it is VERY, VERY Slow especially when nesting a network in another. SD is far more efficient when used to define simpler generators, patterns, filters etc to be used in SP. Problem with both SP and SD is that they require perfect UVs and extensive bakes. It works for games as there is no other way around it, for FILM though this is a limiting factor, requiring asset to be simplified and baked down. It’s faster to render after though and PBR workflow yields consistent result. That might be preferable for scene prop assets.
On the other hand for FILM you can use nodal networks of Maya/Blender/Houdini/your_software_here to define very similar logics in an unshackled environment. For example you do not have to be bound to UV coordinates or a single set, you can use 3D noises, various mesh data (vertex colors, density etc). In that respect to compare Houdinis nodal shading capability to SD would be laughable. That is why it’s important and nice that Blender is also receiving nodes like Bevel (+curvature*) and hopefully in future AO. All of this is pivotal in modern texturing workflows and maybe not in too far future would give certain benefits in using Blender for texturing. For example today I use Blender for Bevel and also often for baking realistic emission maps, translucency/SSS of cloth - things very hard to fake in Substance. All in all using best of all tools is a good practice.