There’s no way any decent DGI solution is going to be multi-platform, and SVOGI wasn’t either. If you’re looking for a scalable DGI solution that extends to Mobile, HTML5, then to Console and Finally to PC, you are completely out of your tree.
VXGI is almost definitely going to be faster. SVOGI’s requiremetns we’re NOT low. SLI’d GTX 680’s for an ‘acceptable’ framerate last time I checked?