I notice the absence of Proteus Bob...Where do you rate that???
Proteus is one of my favorites, but it's a sampler. The bulk of that huge library are natural instrument sounds, and it certainly has its place.
These synths are for those more exotic "synthy" sounds. Think Jan Michael Jarre', Van Gellis, Rick Wakeman.
One thing with most all of these synths, is that a controller is fairly essential to bring them to life.
Velocity, hold time on the keys, and other factors can have a real impact on the sound you get from a given synth.
There's a lot of good stuff available, so keep rolling.