I have both VK and GS. There is a marked difference in vapor production. I don't think you can get close to the vapor from a VK that you will from the GS. I think the GS atty runs much hotter--don't know that to be fact. That would also explain the better flavor with the VK. I refill with a mixture including VG and it is better but still not even close the vapor production of the GS. It took me a while but I got used to the lower vapor production of the VK and now only use the GS when I fly. In case they confiscate it, I won't care. Take the time to adjust to the VK's vapor production and you will like it more than the GS. IMHO
BTW, I have some of the new carts and vapor production is much improved. Still not as much as GS but getting closer. Leaford is a vapor nut so I am sure the vapor will continue to improve with his involvement.