I don't like to store it there. The bumper storage compartment (on both our previous Flying Cloud and our current Classic) experiences some water intrusion and can get pretty dirty in wet weather since it isn't sealed with any kind of gasket material. Personally, I don't want the cable conductors to be exposed to that kind of environment, nor do I want to have to wrangle a heavy filthy cable.
In may we took a 3000 mile trip to Wyoming and back. Lot's of rain, snow, mud, dirty roads, etc. When we returned that compartment was pretty gunked up and had to be hosed out. If the cable had been in there it would have been a mess. TEHO.
I do store hoses for my gray tank and blue boy back there as well as the long rod for the awning locks and the sewer hose elbow.
The thing about science is that it's true whether or not you believe in it.
― Neil deGrasse Tyson
2020 25' Globetrotter Twin
2017 F250 4x4 6.7 max tow Platinum