For me the Redhawk is a .44Mag and only a .44 Mag. I love my 4" stainless, but must confess that if I were to buy again, assuming the same price, I'd find it hard to choose between the 4 and 5.5". The latter's proportions are just fantastic!!
And the sturdiness!!
In .44 Mag, I've never really worked out of the RH and SRH were any different in this respect.
Out of interest, does the RH in .45LC enjoy the same rep for strength as the . 45 Blackhawk? I mean, could it hand similar hot .45 loads as the SBH in .45 or the .454 Casull chambered SRH?