I have both.
One thing to consider is that .44 ammo is more expensive, and .44 special is hard to find at all.
I would caution you to be very wary of buying any Marlin with a SMOOTH stock -- at this point I will only get the ones with the checkered stocks.
The smooth stock ones -- and I own one in .44 and had (sold) one in .357 -- were made to be sold at budget stores (here in Oregon, its "Big 5"), and they don't appear to be the same quality as the checkered stocks. Actually, in the last few years there have been a serious number of complaints about Marlin's falling quality in general, but there were a lot of specific quality issues with the budget models. I can be more explicit with my experiences if you like, but I don't want to hijack this into a Marlin-bashing thread. Safe to say, cycle the lever several times both slowly and quickly at the store before you leave with it, and make sure it cycles smoothly and properly.
My .44 mag is finicky about ammo, and won't cycle .44spl. at all. My .357 (with a checkered stock) works perfectly and will eat anything. If I saw a stainless .357 -- especially one with the laminate stock -- I'd buy that in a heartbeat.