Unlike .38/.357, I've never shot .44 Specials in a magnum. The magnum revolvers are for magnum loads & .44 Spl brass gets shot in the M-24.

I love the .44 spl, but I don't know any reason it would be any more accurate than similar rounds, all else being equal.

Unless you're shooting specials in the magnum for some form of precision shooting, like hunting or silhouette matches, I doubt there'd be enough difference I'm accuracy to worry about.