makho has a video on the power usage of the EZ Flash Omega DE versus some other flash carts.[1] He's also put together a spreadsheet with his results.[2] Essentially the EverDrive would result in a runtime about 90% of an original cart, with the EZ Flash Omega DE coming in at 80%. The original EZ Flash Omega would last about 70% of the time of an OEM game.

[1] https://youtu.be/HrGTzSrdCyA

[2] https://docs.google.com/spreadsheets/u/0/d/1baIDOZlUjERhOsmc...