The Number one in 45/70 is an attractive rifle and was the first of the modern rifles to be brought out in 45/70. The rifle is light and handles quickly.
The Number One is strong. It is so strong, one can load the 45/70 to ridiculous levels (400 grain bullets at over 2000fps). At these levels, that light weight is not an asset and recoil is substantial.
A few years back, I was asked to rechamber one of these to the 45x 2 5/8 Sharps. This takes the rifle into heavy magnum territory if one chooses to load it that way. The customer furnished a box of shells to test it with. These featured 500 grain bullets at about 2350 fps. I fired two then suggested he could do his own testing.
In the end, I think the Number One in 45/70 is a classy rifle in a neat caliber. Loaded to reasonable levels, it is powerful enough for anything in North America and still not too bad to shoot. GD