I've ran 3 beans of each OGK and OG18. I was green behind the ears, and using products I know longer use, but if I were to run them now, I'd probably avoid some mistakes I may have made in my grow. Both are very similar so I'll generalize a bit. The plants were pretty similar in height and lanky, unsupported structure as to be expected with kush (someone can correct me if I'm wrong, I've never ran cuts, but have seen em and smoked em). Yields were low on all of them, they were very sensitive and a tad finicky. The stretch was pretty moderate at about 1.8-2.5 times flowing height. The OGK had an aroma of lemon juice, with little fuel. Now OG18 yielded a tad better (I say that with hesitation as it is NOT a good yielded), had more of sharp lemon juice oder with a bit of a kerosene aroma on the back end. All yielded between 9 and 10.5 weeks. Overall, both will get you very high and stoned. It has that mental shift followed by a heavy body stone. I didn't find it to be long lasting in effects but it was like being kicked by a mule. To be honest, it wasn't bad. So the good, all pheno expression were similar in growth, size, and was a hard hitting high/ stone. The bad: no vigor, slow grower, very picky so be careful not to over feed them as they will punish you with lockouts, burning and possible male parts (only one did this). The ugly: really shitty yield, not a long lasting high, did I mention she is fucking finicky. I did prefer the 18 from just the OGK
These damn seed companies 
