I have the 1895M (450 Marlin) and it has become my favourite deer gun, topped with a Leupold 1.5-5 VX111 with a heavy reticle. I highly recommend a heavy, or thicker type German #4 reticle as it is so easy to use in thick bush but still has slim enough inner wires for fine shooting. I only use cast bullets as I don't understand why anyone shooting 45 cal slugs under 2000 fps wants, or needs jacketed stuff especially at the cost. I never thought about a scout rail and wouldn't bother with it. For me having a short scope mounted above the action balances well and looks very good. I grew up using peep sights but with the eyes getting older a scope makes a lot of sense. If you're shooting heavy loads you'd best get a good scope that can handle it. I've had issues with other scope brands (as have a number of guys I hunt with) so I'd recommend using a Leupold, just my opinion. I doubt you could do better than a 1.5-5 with a German #4 reticle, again, my opinion. Best of luck with your choice.