I have always used 296 in calibers ranging from the 44 mag up to and including the S&W 500 and the results have been pretty good as far as accuracy. Not worried about the temperature sensitivity as I never shoot or hunt below 10F or so. 296 doesnt appear to be the cleanest burning powder but it meters nicely and perfroms well.
But lately been wondering if I am missing out by not trying any other types of powder in the heavies.
What powders are you using with these heavy weights and how happy are you with it?