i'll ignore the fact that the pic comes from a competitors website
Personally I'd choose a DDC pump over the D5
You might also want to consider using masterkleer 7/16 tubing which is less than half the price of tygon and gives a tighter fit around the barbs with no notable loss in flow.
Masterkleer 7/16 is great with 1/2 barbs. Boil up some water, heat the ends of your tubing up and it'll slip onto 1/2 barbs with no problem.