When you sell vapes online, you can't hand-test each unit, so your comparison tests should focus on spec verification, batch sampling, and customer feedback loops. Check battery life claims, coil consistency, and charging behavior across multiple units, and always cross-reference specs with trusted sources.

If you're new to this, start with the basics: verify the specs, sample a few units from different batches, and keep a complaint log. That's the core of online comparison testing.