I can tell you guys in my personal experience with clothing sets containing a number of pieces, it takes me a longer to separate products, and go through beta testing, QA, promo renders and product pages then it does to rig for both, DS and Poser. If I were to try and recover my time, I'd have to charge more to have them separate.

If you get both versions (DS and Poser) in a package, consider it a bonus, rather then something that you would have to pay for extra.

However, since there are differences in production process (pipeline) in making poses, vs add on textures, vs, add on morphs, vs. clothing or whatever else  type of content is out there (this is not an all inclusive list, just enough to get the picture), it is likely going to be up to each vendor to give you what is most efficient and least costly with respect to the process they use.

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Renderosity Store  Personal nick: Conniekat8
Hi, my name is "No, Bad Kitteh, NOO", what's yours?