I think you have to be aware that some DACs could give you that WOW upgrade based on the fact they may have better re-clockers compensating for a budget-ish transport (assuming that is the case in some circumstances).
If you already have a fantastic transport the differences in some DACs is less to do with re-clocking and more focused on the DAC engineering itself.
An example perhaps would be the Audio Note DACs - Audio Notes shun complexity expecting your Transport to be up to scratch - an AN DAC improves significantly with the right transport on the shelf. But if you put an AN DAC on the end of a lesser transport - you are not getting the best out of it.
If you already have a fantastic transport the differences in some DACs is less to do with re-clocking and more focused on the DAC engineering itself.
An example perhaps would be the Audio Note DACs - Audio Notes shun complexity expecting your Transport to be up to scratch - an AN DAC improves significantly with the right transport on the shelf. But if you put an AN DAC on the end of a lesser transport - you are not getting the best out of it.