The REAL is a short bullet, which leads me to believe it was designed to work in slow twists, which it does in my replica 1863 Remington contract rifles, and my Pedersoli 1861. These rifles all twist at or around 1:60 or 1:66, something like that.
However, any bullet that works well in a slow twist is certainly going to be stable/more stable in a faster twist, but not visa-versa. Hard to "over stabilize" a bullet, but accuracy really goes away if it is under stabilized. A bullet can strip, or over-ride the grooves, if the twist is too insanely fast for the bullet and powder charge, but I don't think a 1:48 is in any danger of that.
My best results with the .58 caliber 440 grain REAL, (which comes out of my mold at 456 grains) is with a wad under the bullet (some say theirs don't like a wad) and a minimum of lube on the bullet. Just lightly lubing the bottom two grooves works for me. SPG works well for me. They also seem to shoot well, again, for me, with either the top groove, or bottom, filled with bee's wax and no other lube.
For target shooting, more lube would probably be required. For hunting, starting with a clean barrel, I can get three shots out of the gun for sure, before wiping. I think that's plenty.