There are vendors over at DAZ who still release sets, props, and vehicles in both Studio and Poser versions, but not many and they seem to be becoming fewer by the quarter.
I'm not exactly happy about it, since I cut my scene-building teeth using Poser content, and am, frankly, more likely to look for things in my Poser libraries than the Studio ones. But I can see some point. In Studio, just about everything is a .duf file. So the vendor only has to create a slew of .duf files, and they are ready to roll. For Poser, you have to create a slew of different *kinds* of files; obj, cr2, pp2, pz2, mt5/mc6, cm2, lt2, fc2, hr2, hd2, pz3 -- it just goes on and on. And while I'm not a content creator, I'm sure that it takes more than just choosing from a pop-up selection when it comes to exporting files for packaging. It sort of seems to me that a lot of Poser vendors, who start building things for Studio, gradually stop producing for Poser, since it's extra effort to do it. Of course, if they are selling things through the DAZ marketplace, they aren't being given a lot of encouragement to continue making that extra effort. But in some specific cases, like Stonemason, has started releasing things in DAZ format, but including a package of the .obj files, for Poser users, since the materials can bee applied manually. Very few of his gorgeous sets have moving parts, so there isn't a rigging issue to compound the difficulties.
And, of course, if you are using Genesis figures, you want the duf files. You can throw everything into the same folder with subfolders for components and find everything in the same place. You can sort a Poser library into one folder as well, but most Poser users resist that since they have "grown up" having to hunt for the pieces of one set all over creation.
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