The speed of the graphics "acceleration" will vary with your requirements; I assume that with some functions, it will be really quite a bit faster and with others it won't. I have no experience with Solidworks.

The best way to find out is to install the Fusion 4 trial - mind that you back up your VM prior to trying it out and that you keep your Fusion 3.1.3 images so that you can revert to Fusion 3 if you're not happy with Fusion 4.