in theory, no, in practice, yes.
If there's more than one implementation, there better be a standard, and it's risky to assume any behavior not specified in the standard will be shared by all implementations.
Even with one-implementation languages it becomes risky to assume behaviors will remain the same as the implementation evolves.
Basically, I think that in 10 years, in practice, radix sort will still be faster than quicksort, despite theory saying its slower.