I have not tried the .44 SSP from Remington, as I like a heavier bullet for deer. I have to say, that the 270 GDSP from Speer is the best performing, and most accurate of all the .44 mag loads I have tried. I handload these over a stiff dose of H110, and the load has proved deadly on deer and hogs.
I shoot the same load from my Ruger SA and my Marlin 1894S. I have only taken deer with the rifle, but I did kill a hog last year with the Ruger.