there are some features that are not yet implemented in version 4.0 and there are a few bugs that they still need to fix for it to be 100% stable.
To be honest I have been using 4.0 now for a while and am quite excited about it up until now.
2 features that are not yet implemented is selecting multiple OS'ses for an appstack so you need to create it on both W10 and Server 2016 and the other one is that you cannot use a machine prefix when assigning appstacks.
Also keep in mind that 2.x works very differently than 4.x as it comes to assigning applications.
In 2.x if you wanted to add a lot of applications for a specific user you needed to bond them together and assign them as 1 appstack. In 4.0 you create an application/Appstack per application which is much easier in assigning applications to different users. Logging in with 20 appstacks still is quick.
Thank you for your answer!
We are going to do a pilot with AppVolumes 4 and test our top 10 applications.