Reverse X-price auction - is this a viable business model?

Bidooba.se is closed.
Bidooba.se was a nice designed Swedish reverse x-price auction website. It worked approximately from January till July. Another well-known reverse x-price auction is Dubli.com, which is still in profit, but maybe because of combining 3 types of auction in one website - reverse x-price, zero-price and unique lowest bid auction.

If we compare 3 types of auctions in one table, then we maybe should make a conclusion, that reverse x-price auction is not viable online. Let us see:

	X-price	Unique lowest	Penny
Bidding	Paid	Paid	Paid
Current price	Unknown	You define	Known
End price	Market price	Very low	Very low

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