Your statement is correct and pretty much the first question to ask yourself when trying to decide which way to go.

Other questions are how much driving do you do. Is you truck used for commuting, is that commute further then 20 miles one way. Do you drive cross country or long distances on a frequent basis. If the answer is yes to these and no to the multi diesel vehicle question then WVO may be the right choice.

If on the other hand you drive short trips allot then Bio making may be your only answer.

It will take me about 35-40K miles to break even on my conversion. I'm doing this mostly 62 miles a day. If I could drive 600 miles a day the break even point would be way shorter.