Vidalista 20 mg tablet is strongest, there shouldn't be a meaningful difference in strength if both are genuine and contain tadalafil 20 mg. The active ingredient and dose determine the drug's strength, not the brand's appearance or marketing. For ED: Vidalista 20 mg = tadalafil 20 mg, Vidalista 20 mg the product is genuine and correctly labeled. 20 mg is generally considered the higher as-needed tadalafil dose; it isn't normally taken more than once daily. Don't combine it with Cenforce/Fildena (sildenafil) or other ED medicines. Never use tadalafil with nitrates such as nitroglycerin. If you're asking about different Vidalista 20 brands/sellers and which one is most reliable, I can help you compare them.