I also love that you don't build a tolerance to it. Combined that with the fact that Early Queen gets better with age and you have happy pot that actually gets you more stoned today than yesterday. Opposite of most pot. Most starts off great and fades quickly. Early Queen starts off meh and builds to Fantastic.
The plants will be mostly short and the buds will contain a large amount of leaf. those two things should help you identify which is which. Early Queen also has a unique smell. That will help you identify any taller plants too.
The leaf in the bud is what prevents it from having Fantastic bag appeal (just so-so bag appeal) But it is a testament to the sativa genetics contained within.
I also like the fact that light smokers can (and do) enjoy early queen, just as much as I do. Again Happy Pot. Who doesn't like happy pot?