I'm not sure what Marker bindings you have, but race bindings tend to be heavier than regular bindings to begin with. A single duke (with screws) weighs 47.1 oz (2.944), while a single trekker weighs 20.81 oz (1.3 lbs). I would assume that the marker + trekker combo is going to be heavier than the dukes, but at the same time, 189 hellbents are more ski and heavier than the sickbirds, so it might even out in the end. Its hard to tell. Me personally I would go with the hellbent/duke combo unless it was very firm snow because in the end, dukes tour way better than trekkers, and ski really well too. I've never ejected or prereleased out of my dukes. They're pretty solid.

From Below: From Wild Snow.com"If you've done much backcountry skiing, the first difference you'll notice about using Trekkers is the weight. A conventional alpine ski setup, combined with the Trekker, can yank at your feet like a torture of the Inquisition. I calculated one rig, using my heavy alpine skis, at over fourteen pounds per foot!"