I favor H4350 over IMR 4350 in short action cases,like 7mm08,and IMR over H in long action like 270. It seems to me that velocity is better ,and accuracy just as good with H in my 7mm08 than it is with IMR. I'm not talking about overly hot loads either. I have the Lyman 49 the edition,and they have H4350 in their burn rate chart,but of all the data I have looked at in the book they list no loads using H,but plenty using IMR. I use the Hodgdon online data a lot,and they do list it in many loads. Is H relatively new,and just not as much printed load info for it,or is there another reason for IMR to seem to be favored? I have been loading for about 7 years,and I bought some not too long after I started.