From a players perspective it's a bad idea, Shadow is clearly the better game (my personal opinion, Pinside opinion & IPDB opinion).

From a value perspective it's a good idea, Congos sell for slightly more than Shadows (at least in Europe).

I think the statement above says it all - because that's what Shadow is all about and what makes it such a great game: The challenge, the modes, etc.

Nice!

It's strange though, Shadow is the one pin the newness hasn't worn off at all even after more than a year into owning it.

Great point! I was trying to put my finger on what makes Shadow so great apart from the obvious mechanical creativity (diverters, mini-pf, ball-lock), and it really is the intensity of the gameplay with the sound adding even more punch to it.

It's not a game you play a laid back relaxing game on while having a conversation and drinking a beer. It's a tough rush of a battle that will immediately punish you for even just a split second of distraction. In my book that's pinball at it's best.