You can get the smoktech 1.7ohm cartos from Crystal Clear Vaping for a really good price. He calls them the "ressurector" cartos. They also have free shipping which is nice when you just want to order cartos. They give you a free syringe with all carto purchases and if you get a 15-pack you get a syringe and a free drip tip. It's a really good deal, plus he guarantees all carto purchases. I buy all my cartos there. The Ressurectors work great on the kGo. I use them on an EPower, which is a similar 3.7V PV to the kGo, but uses non-proprietary batteries. The Ressurectors are the only carto I use. They are single coil, but many people feel they produce vapor similar to a dual coil, and they wont drain you batteries like a dual coil will. They hold alittle over 2ml of juice so they last a long time. I fill 2 in the morning and I'm pretty much good all day. I think you'll really like them bc they last a long time, but you'll still be able to carry them and your pocket. I really like them for that reason too. Carto tanks are nice bc they hold alot of juice, but their kinda big and harder to carry in your pocket when your out. It's easy to throw a few Ressurectors in your pocket and you'll be good all day. They last a long time too if their filled correctly and used properly. I get on avg 2-4 weeks out of one Ressurector. You do have to make sure their filled correctly, and the first fill is very important. I recommend either using a syringe to fill them or the condom method. If you drip into the top of them, you have to let the juice settle and it takes a long time. Also you can ruin a carto that way if you don't wait long enough for the juice to settle. I use a syringe to fill all my cartos, especially for the first fill, and then I occasionally drip into the top when I'm just topping off a carto. The syringe you get for free from CCV is perfect for filling. Filling with a syringe is very easy to do and you don't have to wait bc you put the needle to the bottom of the carto and fill from the bottom up. and since a syringe fills from the bottom up, you take away the chance of ruining a carto bc you didn't wait long enough for the juice to settle