It all depends upon what your company wants or allows.
We did a DP ferry and were allowed to got to FL250 on O2, no so bad.
We also did a ferry but were limited to FL100...... and hence 250kt.....
it took forever to get anywhere......
multiple stops weren't bad though
If low, then no O2 and much higher fuel burn, less speed, much longer.
Depending upon why you are ferrying DP you will always get the , whats that noise.... have you heard that before paranoia that the thing is falling apart around you
just get the engineers to add more speed tape!
