It depends on the content of the amiibo I guess.
Marth is pretty valuable if only because of FE Fates and Codename Steam.
Meanwhile, while Mario is compatible with several games, the features the Mario amiibo provides isn't too substantial in most games, so I don't consider him that valuable or worth the cost.
"Just for comparison Uncharted 4 was 20x bigger than Splatoon 2. This shows the huge difference between Sony's first-party games and Nintendo's first-party games."







