This article has been updated after I received input from project leader Dr. Alexander Colsmann. He is the head of the Organic Photovoltaics Group at Lichttechnisches Institut, Karlsruhe Institute of Technology (KIT).
It seems to me that the only real metric that the market pays attention to is cost / Watt. If the the organic cells are as efficient as silicon and the same or lower cost then they will gain market share. Perhaps, in the short run, they could make inroads due to their flexibility but the bottom line is the bottom line.
Theoretically, the current level of efficiency of the organic solar cells will only make sense if the cost of production for the organic cells is more than 30% to 50% lower than the same for their inorganic counterpart. Flexibility is plus point but the researches need to push the efficiency further up to make this as an attractive alternative.