This is not the dead of full frame. Metabones aren´t cheap. The EF to Nex adapter cost about 500usd. How much this one would cost? 700?
1000 USD camera + 700 adapter cost almost a full frame one... (If you buy a 5d mkii is the same price...)
But the adapter is a huge step if you have some good full frame lens and want a new small body (to travel, etc...)