Is a UD or any other good log style vape better than the EQ, or DBV?

Better in what way? Would you ask whether a shotgun is better than a rifle without qualifying it by saying what you want to shoot? All log vapes aren't the same, and the Extreme and DBV are quite different in their design and strengths. It's such a wide open question you may as well be asking 'what's the best vape?', and there's no answer to that without narrowing down the performance/features criteria.