They are official Nintendo toys that allow you to get new (although tiny [skins, weapons, etc. for the most part]) content for your 3DS and Wii U units. That's the value of these figures.
I'd say you should get those ones that have compatibility in more games, such as Link, Mario and Kirby.
My bet with The_Liquid_Laser: I think the Switch won't surpass the PS2 as the best selling system of all time. If it does, I'll play a game of a list that The_Liquid_Laser will provide, I will have to play it for 50 hours or complete it, whatever comes first.







