Yeah, The Daymaker Alpine Adapter is 800g per ski + your binding which is typically 1000-1200g so you're spot on. 1800-2000g per ski.
The cast system is 180g + 250g dynafit toe + your binding heel (500-600g) AND your toe piece in your backpack. so that's 930-1030g per ski and 250g in your pack while touring.
overall, you're looking at the daymaker adapter having 750g more weight than the cast system. The Fall/Early winter 16/17 run will likely drop our weight of 800g to 650g for Stainless Steel version, and 450g for the titanium
However some pros of the daymaker
1) transferable between all your skis
2) Standing height + 2 other incline heights VS 1 hiking height. more adaptability to the terrain.
3) Transferred carrying load to more under your tibia reducing the moment arm (torque of your ski depending on the placement of where the binding rotational point is) placed on your quad. This reduces fatigue
4) An increased normal force to the snow during uphill travel while your body is shifting into its next step. The 4 bar creates a larger platform to stand on and shifts your pivot point under the balls of your feet rather than your toe or in front of your toe. Moving this point back allows more of your weight to be above the center of your ski while taking an uphill step.
3 and 4 are direct results of a 4bar linkage versus a traditional single pivot design. I'll be updating with graphics and technical drawings in the near future!!