Maybe this ID page will help. What I, as someone not familiar with the plant, other than having grown Magilla years ago, noticed is that the teeth on the leaves look different. They are more even in size and spacing in the pictures of Perilla frutescens but vary in size on the ID plant which even looks doubly-toothed in some areas. According to this ID link there should be a single groove in the stem (not clear on the ID plant but may be there) and the flowers should be two per node. The flowers on the ID plant look like there are more than two per node but again it's not entirely clear in the picture.
Page on IDing Perilla frutescens:
http://www.missouriplants.com/...
Compare also this pic from the database, especially the teeth:
