I had read that IMR4451 was supposed to be comparable so I gave it a whirl. Great results. Same ridiculous precision, similar MV. Haven't tested it for temp. sensitivity but it is part of IMR's "enduron" line which is supposed to be their version of Hodgdon's "extreme" line so I would imagine it's not bad. They are not 1 for 1 as far as how much to use goes, so you'll have to work up like anything else, but for me it ends up being about .5gr less. This is in my .260 so I can't speak to other calibers but for those of you shooting 6.5 creedmoor, the .260 is very similar. I ordered an 8# of the stuff.