This is a great way of adding man-power and development skills to Darkcoin, the merger-acquisition would be proportional to the SDC market cap at the time the deal was finalized so it can't really be manipulated. It just give all of the SDC community and developers to join DRK and convert their value, together we stand... divided we fall. This way they dont loose any of the effort they have put into their own project but preserve that value by joining DRK and ensure that they endure the consolidation that is happening on crypto right now, if they dont take this opportunity they run the risk of just dissapearing. I think is a win-win.
However, if between now and that finalized day, SDC rises to say 1-2 million, that's 1-2 million worth of DRK created on a pump. So from this swap, the SDC holders would realistically be making 2-4x as much money being that they can then take their newly inflated coins and sell them.