Call me a optmistic, but... first off I will agree that for $20 that would be crazy (if it had Super Dodge Ball, however, I would be all over it). However, let's assume it's released in the US, these carts would most likely be sold for very cheap used. Personally, it would be hard for me to pass up a $7 used copy of this.
Anyway, as others have stated, this cart should have WAY more games on it. If they would have thrown in Super Dodge Ball, Punch Out, River City Ransom, Fire Emblem (translated), Fire Emblem Gaiden (translated), Famicom Wars (translated) and the NES Tetris (simply beacuse I would be to lazy to dig out the GB version), then that would have been a awesome package, and more than merit a purchase.