Here's an example. This literally took only a few minutes to paint, and a sloppy job, but it'll serve to demo the interface...

You import your model, in this case its LF's face mesh. It could just as easily be an entire figure, If UDIM it paints across uv borders seamlessly. As you can see there is a viewport and a scene hierarchy similar to Poser...

There's a tab called layers that has sculpt and paint layers. If you select paint and the painting tools you'll be presented with this...

Above I already have some layers set up. You can create a new transparent layer, in various formats such as diffuse, bump, etc, or import layers in a number of formats, including psd. You can also export or save likewise.

Below shows a menu for various functions dealing with painting, very similar to photoshop. You also bridge directly with photoshop via this menu.

The number of tools available is too numerous to go over but you can projection paint from photo resources directly on the model. It's an involved process that takes a bit of work but it's entirely possible to fully texture a figure model from photo resource without all of the fussing with seams.

Another tool is your fall offs for your brushes. Besides the ability to create custom alpha brushes, use abrs, you can also completely control your fall offs and save custom presets

Some sloppy brush strokes applied to a layer with a simple brush...

This software is a steal at 10 dollars a month especially since it's a fully featured sculpting program. It was originally developed by WETA digital to do the effects in King Kong and other film projects they were working on. Since it's been aquired by Autodesk they haven't updated it much but I'm hoping it doesn't fade into obscurity, it's really wonderful. My favorite actually, and I use Blender and Zbrush but do all of my painting and most of my sculpting in it. 

Anyway, just something to consider. It's not a gigantic investment to give it a spin.