Do you find that the high THC plants get you the most stoned?
Super Silver Haze for example is listed as 21% which wouldn't make it into the top 5 weeds in the dispensaries that sell by THC content, but a well grown pheno is an excellent weed that will absolutely blow your head off.
The more organised dispensaries are using the Purplpro THC testers which are accurate to about 3% compared to labs, so generally offer a reasonable guide.
Not sure what that is actually worth though, the best weed is not the one with the highest THC level, imho - it's the one that has the best grower growing it.