Coroplast DDust/Whiplash -- Cheap Speed!
That's a nice looking coro-delta. It looks like a dust, and is cheaper but it won't fly like one. The DD has a big advantage, weight. My DD weighs 31 oz. It's 24 oz (1.5 pounds) lighter than the coro-dust at 3lbs, 7oz That makes a big difference. You'll need more static thrust to get it in the air so won't be able to prop it as fast as DD.
It's not just power it's power to weight that makes speed. I'm only using a Thunder Tiger .36. It turns an 8-6 right at 17K and has more than enough thrust to get the DD into the air. I thik it's pretty cool to take a $75 motor, add a $30 tuned silencer and bolt it on a $65 dollar plane and go Very Fast. Spending 5 dollars on an air frame for a $200 engine is still less speed per dollar.
I was seriously considering the Whiplash but ended up staying with the DD because of the weight. You need a lot more motor to go the same speed.
Tom