Greetings,
I have used WST ever since it replaced 452AA.
Never had any issues with metering. Actually, it meters very well. I load the 32 S&W Long with 1.62 grains. 38 Special gets 2.8 grains. the 45 ACP uses 4.3 grains. Again, never had a problem.
I always remove the powder from the hopper when I am done loading.
Cheers,
Dave