I guess the question is can you justify $50000 for equipment and how quickly can you get a return. Must be selling some big print packages to fund it.
If you already have one a studio camera then fine, but the images sizes I print a D3X or indeed D3s is already too much. I think the optics will show a difference, but the speed of the Weddings some shoot will tell me the kit will only come out at the slow or arty moments.
I would love to shoot on a 645, Phase or indeed S2 but sadly to cost of entry is just too high.Some parts of the Wedding will benefit but most of it will not. You must ask yourself if photographic royalty like Jeff Ascough or Joe Bussink or Dennis Reggie including the new wave of stars like Mike Colon, David Jay, etc dont use them, there is a reason.
I think its a nice gimmick, but the bride is unlikely to see or appreciate the difference. An editor will see the difference as will a fashion client.
Just sadly my 2 cents worth, I so want to justify one.