While I think the Marlin is probably better built, the Ruger has it's advantages as well.
The action is quite a bit faster, and the rotary mag, means you can unload/load quickly.
The mag on my wifes Ruger holds four I think, giving you a total of five, with a loaded chamber.
The Ruger is about as light as you could want with any rifle, and that means it has substantial felt recoil. Not helped by the design of the stock, wich I guess is Rugers interpretation of a carbine butt.
accuracy with any 44 will never get you a huge prize, the Ruger that my wife owns, manages three inch groups with some regularity now. Ok for close range work, but that's all.