This powder shortage has given me the opportunity to try new powders, including some of the new IMR temp stable powders with copper fouling eraser. I'm using 4166 (replacement for Varget) in my 7mm-08 and 4955 (replacement for H4831) in my .284 Win. I have zero complaints. Nobody knows what those powders are yet, so they sit on the shelves. Just fine by me.
The 4166 is an almost identical replacement for Varget in my experience. Same loads, same groups. Great stuff.
I was a bit skeptical of the 4955 at first, but it's grown on me. I am consistently getting 3/4" groups or better from my .284 Win with it and it's nearly identical to Hunter. Same load charge, same result on paper and over the chrono, at least in my rifle.
It's nice to have options when powder is in short supply.