Glad to hear you are enjoying your cartotank.

It's all I use now. I have seven of the 19mm IBTanks now, each with their own flavor and it is so easy to change flavors by simply exchanging tanks. I have the different colored acrylic endcaps and colored drip tips to help me remember what flavors are in each tank.
Each tankfull lasts me 2-3 days, and I can refill the tank 3-5 times before needing to change the carto out for a new one. Keep in mind these tanks only hold approximately 3ml of juice each. I've found this to be the most time-efficient way to vape, as it only takes a minute to refill a tank, and perhaps 4-5 minutes to set up a tank with a new carto (the tank tools really help in this regard). Not to mention the cartotanks provide me with the best flavor and vape I've experienced of all the juice delivery devices that I've tried, including the vivi tanks.