The nickle plated brass can be reloaded - I have have been using to reloaded for 20 years. However, it is a bit harder than brass and will wear on your dies. Make sure that it is clean also. It will split faster than regular brass and you will get fewer reloads out of it, it its safe and good to go. I generally stay with name nickle brass, fed, win, r-p, etc.
Some people do not like the nickel plated cases. I prefer them. Clean them well and they will not cause undue wear on the sizer die. Carbide is WAY harder than nickel. Life expectancy may be shorter but I generally get 5 or more loadings out of nickel plated pistol brass. That's good enough for me as I usually lose them before they get to that age anyway.