Will it always work?
Why not?

I have created RROUND.PRG like this:
Lparameters m.nNumber , m.nPrecision
Return Iif( m.nNumber < 0 , ;
-1 * Round(Int(Val(Transform(-1* m.nNumber*10^m.nPrecision+.5)))/10^m.nPrecision, m.nPrecision), ;
Round(Int(Val(Transform(m.nNumber*10^m.nPrecision+.5)))/10^m.nPrecision, m.nPrecision) )

All my code uses RROUND instead of ROUND. I have not been able to find any problems with this.