From what I heard, the tooling in the Marlin plant was pretty much clapped out when Remington bought it and all the employees that knew how to nurse the machines along had been fired. I have no sympathy for Remington, but it sounds like they were sold a bill of goods.
I don't know if they're continuing to work on the worn-out tooling, or if they've tried to convert it over to new manufacturing processes and had teething issues, but it sounds like there's reasons why most of the new Marlins have been so defective. And that's not including the management team that's focused on 90 day profits and couldn't care less about the long-term health of the company.
Hopefully they get it straightened out, because Marlin really does have some great guns to sell. I'm not a 336 fan, but the 1895s in 45-70 and the Model 60s are classics.
If you just want a 45 LC lever gun, I'd get a Rossi 92 in that caliber. For reasons known only to them, that's the only caliber they even sell the 92s in any more. They're just fantastically lightweight, fun guns. They're known for being rough from the factory and having dodgy QC, but at this point, I don't see how they would be any more of a gamble than Marlin.