Sour D, OG Kush, Elephant Bud (never seen a grow, but heard you can get 1100g sq/m).....Umm there are many of them. OG Kush, OG #18.....I can go on for days

You gotta remember though that it's also many factors such as your growing medium, nutrients, lighting, how much light, temps, humidity, veg time, etc. Again I can go on for days. What they say is just an estimate at what you can get with OPTIMAL conditions.