Well... If I go with powered risers whats the point of buying H81 Btc Pro if it's not for using its molex connectors on board. I can just buy cheaper one and go with powered molexes... It would be the same thing.
And it would actually be worth something when you went to sell it in a few months/years.
That board is a gimmick for noobs, as pointed out previously.
Not necessarily. The retail price of that motherboard is 69 bucks, which is much cheaper than other 6 gpu capable boards. It's not required to plug in the molexes on the motherboard since they only supplement the existing 12v power from the ATX connector.