Kosher Kush easily gets my vote...I've grown out Cataract Kush, Stacked Kush, OG#18, and several other Kush offerings from various seed banks. Kosher Kush was by far the best as far as quality is concerned. I do have to say its yield was rather dismal, however. If you want a high-yielding, yet really potent kush variety, I would suggest the cataract kush, but make sure you veg it for around 2 months. You can easily pull 4 oz off of one girl, and it is complete knock-out quality.