Why is House of the Dead: Overkill a full price game?

[Hawk]

I hear good things about this game, but I'm waiting for the price to go down before I buy it. The game being short actually is what makes it a sale for me. Once the price is about $20 that is. I like light gun games, but only for a short time. I tire of them really easy. So I'm glad I should be able to play this game through in the time that I still find it entertaining. But I will only find $20 my selling point for the short time of fun I expect for this game. But that's not really an indication as to my thinking the game doesn't have value, it's just an indication of my short attention span for light gun games.