Last night I completed an update to the secp256k1 NuGet package. This allows us to easily run the latest update to the library in the vc++ builds. I've run a few full validation/confirmation syncs on the maxi since then. The difference is a reduction of about 10 minutes over the course of 5.5 hours.
The vc++ builds pf secvp256k1 do not have the advantage of the asm optimizations, since vc++ does not implement assembly in x64 builds (optional part of the c++ standards). Also, the run is limited by confirmation, not validation. I will perform some non-confirming runs just to see what is the actual improvement.