Download and discussion about BeamSyncDropper can be found here: http://www.tonymacx86.com/customization/92201-beamsyncdroppe...
Also one thing about OS X running in VMWare is make sure you're using the specific CPU to the fullest potential. Graphics are rendered with the use of CPU. If you don't have the processor(s) / cores set properly you could be only at 50% overall performance. For example, I am currently using an i3 330UM. I've noticed a significant jump in performance switching from single processor 2 cores; to 2 processors 4 cores.
Personally, Mavericks outperformed Yosemite on this little machine. I've experienced long window load times, hangs, and even guest crashes since the jump... My main desktop workstation is rocking an i7-930; I WILL NOT upgrade my main VMWare workstation to Yosemite. If I need to I will just clone my current VMWare image and run Mavericks / Yosemite in tandem. I would much prefer Mavericks > Yosemite...
I put this [1] in `~/Library/LaunchAgents/self.beamsync.dropper.plist` and it starts immediately in the background on login. (Make sure to change the program path).
I also feel that since iOS 7 that stability and quality has gone down a lot, or they got too ambitious with the glass blur effect.
They've just removed the last remnants of pure 2D acceleration support in Yosemite, it's HW-accelerated OpenGL or nothing now. They also changed the timing of screen updates, which locks some drivers at 8FPS. Finally, the rounded corners on windows seem to be broken in the software renderer.
Before you go blaming VMWare etc. for not offering an OpenGL driver: Apple doesn't document those APIs at all, there aren't even headers files. They don't even officially support writing a graphics device driver at all (according to DTS), but they provide enough source code so you can figure out how to do so, albeit not providing 3D acceleration.
Bugs and generally poor software quality, however? Yes.
They said at wwdc that the blur effect took a lot of 'optimization' work. You don't have a lot of control over how it works and in iOS 7 you had to hack it in by using a UIToolbar vs applying it to a UIView in iOS 8. If you have any view with a significant amount of the blur effect on screen, the animation speed will slow down considerably in the simulator.
They use the effect everywhere in iOS and I bet it does contribute to a decent chunk of performance reduction.
When running OS X virtualized inside VMWare Fusion (which does not have hardware accelerated video drivers for the guest), Mavericks was very usable. Yosemite dropped to 2fps (measured using Quartz Debug tools).
I had to use Quartz Debug (available in the Graphics Debug Tools here [1]) to disable beam sync to make it usable again. In VMWare, this takes me from 2fps to around 50fps for basic operations like dragging a window around and typing.
I've observed noticeable improvements disabling Beam Sync in a native environment as well. Unfortunately, I've found no way to do it without leaving Quartz Debug open. Quartz Debug also has an FPS meter in the menu bar under "Window -> FrameMeter". My framerate when dragging a large window in Yosemite with "Beam Sync: Automatic" is around 40fps. With "Beam Sync: Disable" it's almost a steady 60fps.
A stable test in System Preferences for me is the Dock settings.
[1] https://developer.apple.com/downloads/