I own a 45-70. Out to 150 yards, they are very accurate and easy to shoot. Beyond that, you get into the scary parts of the 45-70 ballastically. You can learn to shoot them beyond that but for me, 150 is about all I'd need it for.
As far as the stock, a little stock wax should cover it. Otherwise, try not to beat on it and you have no worries.
They are fantastic guns and there is zero reason not to take them out and enjoy them.