I have the Chinook and have tried several aftermarket cords. Can't say I can really tell much of a difference. Power cords seem to do a lot more with SS gear than with tubes.
For the Chinook, if you want an easy upgrade, swap out the TL082 op amps at the rear of the unit and replace with Sparkos Labs discrete modules. The remove several curtains of grunge over what the TI parts do... and best off all, no soldering, simply unplug the stock units and insert Sparkos modules.
well work it