I have both cartridges and to tell you the honest truth there is little to be gained over the 7mmstw with the 7mm ultra.I get over 3520fps with my faster stw and 3560fps with the ultra(140gr bullets) for a 40fps increase which is not much for the extra powder burned.I find my 7mm ultramag prefers h-1000 while my stw's prefer imr7828 and my 300ultramag prefers r-25.