I finally switched and upgraded to Cantabile 3 and can say that I'm very happy .
This software is a blessing for performing Windows musicians.
The software is very stable.
Loads and switches very fast. Can preload the setlist with all the plugins. Switching is a matter of seconds.
Very low latency.
There's an enormous user community, very helpful and mature, the developer is always and I emphase ALWAYS there if you have some issues, ...
Everything is MIDI assignable.
Good playlist manager (separate text files you can edit, so crash proof).
Song structure is very well written: You have Playlist > Songs > States (=parts in the song, f.e. verse, chorus, etc.).
Engine is stable and written by a musician, so he knows the problems on stage and has workarounds for it. f.e. the audio ports are linkable in the options, this way you can easy change your soundcard without reassigning all the settings. Racks are plugins structures you can link and reuse in songs, loads faster. Also, there's a Background Rack, here you can add your basic settings for the whole show.
Built in Mediaplayer .
Built in Notes viewer.
What more can a musician ask?
Sure, it's not as sexy as Mainstage or other hosts, but it's very powerful once you get past the aesthetics.
Switching to C3 is the best thing I ever did, finally a decent Windows VST Host .