Here is example of making one object in group unique:
Also in recent 1.02 version, you can make whole group unique. See last image in first post.
And yep, this is how I wanted Group Instances to work in blender, but default UI for it is not exising, so I had to code it myself.
NinthJake - btw. Blender will render those ok, but baking is not supported, so I made another addon for that. Free version of addon for baking is here (cycles baking- bit slow):
Paid version (baking through Substance BatchTools) is here:
Thing is, I give promotion code with Batchtool addon (it was just released yesterday), for GroupPro discount. So if you have Substance Designer, you can buy BatchTools + GroupPro with discount for 12$+(48$-14$) = 46$. You will save 2$ and and have both addons. Or just go with regular GroupPro and free Meltdown fork from github, if you do not have SDesigner.
Also form time to time (eg. on Black Friday) I make discounts too, if you want to wait for Christmas that is…