My original 39A dated back to before WWII and did my original 336 .30-30 and .35 both were from the time period before Ralph Nader changed every facet of our lives. All were stolen in the mid-nineties and have been replaced with the newer model and, in addition, an 1894 .44 Mag.
I prefer not having one since the guns I grew up with didn't have them. In fact, I will probably get the kit and remove them from all three of my Marlins. I don't happen to like the rebounding hammer, either. Doesn't look natural to me.