In my experience, accuracy-wise they are very close. Disclaimer: I am not a good shot. My Savage MKIIF does about 1.25" groups at 100 with Winchester White Box Dyna Points on a good calm day and my eyes had a good 8 hour sleep. My Marlin 981T, which I think is the tube mag version of the 980, does about 1.5". The Savage Accutrigger is better in most ways a trigger is measured....lightness, crispness, overall feel.
Perhaps the better trigger is the reason the Savage groups better. Their accuracy is that close. Another person may shoot the Marlin better. Or maybe in time, my Marlin triggers will improve. Mechanically, I think that they can be equally accurate if their triggers can be made to feel the same.
However, I prefer the mechanical feel of the Marlin, smoother when you operate the bolt. More solid and robust, substantial feel to the whole rifle. The receiver looks thicker on the Marlin as well. Fit and finish is better on the Marlins IMO. I bought the Savages because of the trigger and Savage accuracy. I bought the Marlins because I like Microgroove bores and Marlin rifles.
I got 2 x 981Ts and a MKIIF, MKIG and a Lakefield 91TR which is very similar to the Savage MKIIs, to compare.
I doubt you'll regret buying the 980scf.