Upgraded RX580 rigs to the new driver and Claymore 10.3. All works fine getting the same hash rate. Cast XMR 0.8 works fine too, same hashrate, had to add --forcecompute and --opencl=1 options to make it work.

However the Vega 64 rig doesn't work with new driver, apparently the issue is in Cast XMR miner. First of all it doesn't work with "--forcecompute and --opencl=1" and the vega cards, don't know why. But haven't had much time to play with it though. I think there should be the way to make it work. The miner just hangs or complains on --opencl=1
And also devcon doesn't disable/enable the drivers programmatically(actually it hangs when trying to enable them), which is probably not needed with new driver.