I know the JM stamps are bringing higher $$. Also when Rem first bought Marlin out the quality wasn't there but after some machine revamping the quality improved. That's what my SBL is (a RemLin!). Now that Ruger has them they have changed them a bit. Like IdahoRon said they went back to ballard rifling at least on the SBL.
Besides my SBL I also have an original JM stamped 1895 Guide Gun with the ported barrel. I'm sure that one would bring a real premium price if I decided to sell it.