The hyperdrive to me is the best solution if u just wan an OTG portable storage. Look at the older version such as Hyperdrive space instead of the newer ones like colorspace album. Memory world might not have the older version but u can check out the Hyperdrive website. They do ship overseas when i bought the super duper old hyperdrive space >5years ago. It does not have the screen to view the photos or the super fast speed. So depends which u value more. Big viewing screen and speed requires at least the Hyperdrive colorspace O if i'm not wrong.
Ipad max storage is pretty limited. If u goin for a couple of days trip guess shd be sufficient. Anything longer than 1 month, i doubt so u have ample storage.