I have both Poser and Studio. I tried studio, but I am much happier with what I can do with poser. So, when DAZ came out with free Studio Pro, I downloaded a copy but never installed it...and I don't really think I will.

I own PP2012, and have the DSON plugin, but I never installed the plugin. There is too much risk of something breaking that pipeline in the future, so I will never spend money on content that relies on both DAZ and Poser's owner (who knows who it will be next year:) ) being in cooperation. If you don't believe me, just ask vue users who upgraded poser shortly before a new version of vue was released. If you wanted to retain that functionality, you were going to have to outlay for 2 upgrades...too expensive for my blood. Studio might be free today, but who knows how much it will cost when it's time to take advantage of the next version of poser. And, if you can't afford that upgrade the plugin, you lose all of your content, I would imagine. Maybe it won't be a problem, but, unless you can see the future, you should keep it in mind as an option.

So, I'll use V4 and M4 until there is a better native set available that has the market support that the mil4 figures have had since almost the beginning (which will probably never happen) SM was supposed to be looking into doing just that, but who knows how it will pan out if/when they are released.