Walmart also sells an oil drain pan next to the funnels that has quart marks on the inside. This will help see right away how much was drained from your DSG so you know how much to put back.When buying online, I find that autohausaz.com comes in with the lowest overall price for me virtually all the time because of their free shipping for orders over $50.
For example for the 40k service: air, pollen, oil, fuel, and DSG filters, DSG gasket, 5 liters of 507 oil and 5 liters of DSG Pentosin fluid comes in at about $226 shipped to your home. For a manual (removing the DSG stuff), the price would be about $113 from autohausaz. If I buy the 507 oil at my local Pepboys, I can save another $5 or so.
In addition, doing a DSG top fill with a Walmart funnel instead of "making" a DSG fill tool will save one about $15.
Also when I drained my DSG the plastic overfill tube was not screwed in all the way.