Well I've got the Insider release on there, and our VFP9 SP2 main application and the VFP IDE seem to be operating without issues. It doesn't seem that much different, a bit faster maybe although that may be because it refused to upgrade with our corporate McAfee present so I had to uninstall that first. Reading up on it it seems most of the changes are targeted at the consumer versions of the OS whereas I'm on Enterprise.