I don't have the experience of some here, but I have used W296 for a while in .357M, .41M, and .300BLK. Seems to work well, but seemingly very little room for adjustment...maybe a grain or so. Go big or go home loads.
Although I have owned a couple pounds of 2400 for quite some time, I never tried it until I bought a .38/44HD recently. The 2400 was highly recommended, and it seems to have a lot more flexibility--legacy loads from 10.0 to 13.0-13.5 gr, allowing a good bit of room for experimentation.
Also, no need for Mag primers. Love that.
I have room for both in my locker...2400 for .38/44, W296 for full-power .357. I will also use the W296 for .300BLK and a few others...it won't go to waste.
Great to have choices.