I only used it to get rid off some rupees when I entered a Dungeon. I wanted to open all chests hidden in the dungeons without the But it won't fit your wallet message It is pretty cool but you got to use it at the right moment
The moment it said it needed rupees to work the greedy part of me completely and utterly REFUSED to even buy that thing, But I HAD to get it for the 100%.
I literally never even considered about using it, theyre my hard earned rupees why should I just waste them like that?!
I saw it in the store on the game, thought about it and got a second opinion from Zelda Dungeon's walkthrough and I didn't even get it. I found it unuseful and plus I never got much rupees, only when I needed them so I didn't see a point in buying it.