Head to head tests.  Real world results.

The worksite doesn't care about a pickup truck's spec sheet.  What does matter is how those numbers translate into real-world results.  It's one thing to know how well heavy-duty pickup truck brakes work when they're under light-duty conditions, but what about their stopping power after hard use with heavy loads? Or what do torsional rigidity numbers mean when you're hauling cargo out of a ditch?