Negative so far on the 45 Colt SB1 from H&R, most likely due to too much temptation to rechamber to Casull or 460S&W which have double the pressure of the Colt +P. To do one yourself I don't see a problem with it since the 44mag has higher pressure and there's not a lot of difference in case head size, .457" @ 40kcup for the 44mag vs .480" @30kcup(+P) for the Colt.
Tim