Explaining it from the viewpoint of another user so my view is not cast in stone. I also have the entire suite of Topaz plug-ins. Eventually, all the plug-ins will migrate to Studio as they are upgraded to achieve a common engine which will be easier to maintain. The upgrades will be free as always but the originals will not be supported. They will be able to used as long as technology allows. The new Studio versions are faster and improved. In the interim, ALL original owned plug-ins are available to use through Studio. The free version of Studio offers some basic Adjustments without charge. It also offers some very limited abilities of some of the features of the plug-ins. The Pro version expands the amount of controls within the Adjustment.but they do not equate to the total functions contained in the original plug-in. At this point, as they are upgraded to Studio, the corresponding Pro versions become activated. At any time, a trial copy of the Adjustment Pro function is available to download for 30 days and can be compared with what the corresponding owned plug-in offers. If it duplicates a function, there is no need to purchase the Pro Adjustment unless impatient. Obviously, if it is something brand new and would be useful to you, you'd purchase it.
Offered both as a standalone and a plug-in, the goal I believe is to eliminate the need for a separate editor down the road for those who do not get into more complex nuances. The tools they need will all be under one roof. When the transferring of the plug-ins to Studio is complete, I expect that new tools and abilities will be added. Studio is an evolving application.
If anyone finds that my take is mistaken, please feel free to correct it.