Tanks are fairly easy to use. You'll just have to find what works for you to punch, drill, poke; a hole in the carto. I use DCT tanks that I cut down to size so a standard size 3.0 ohm Boge fits them. These tanks are inexpensive and easy enough to fill using a syringe. (I think
my4jewels was a pioneer of cutting these tanks shorter). I don't like dual coils, particularly with a ProVari and I don't like XL size standard carto's. The juice seems to cook in the tank when using the XL size carto, and can turn dark / off color before I finish a tank. A carto will last longer when used in a tank, but you'll still have to change it out occasionally.
These are both 3.0 ohm single coil carto's loaded with BWB Malty. The XL carto/tank has turned dark after a couple weeks of use. (Anyone else notice this with their XL or DC carto's in a tank?)
A popular alternative to a traditional tank is the Stardust class mini-tank/CE3. My wife uses these exclusively and highly recommends them to her vaping friends. They last a long time, relatively easy to refill, and give nice flavor and vape. I tried them and think they are better then a carto/tank. But I don't use them as they don't work for me well on a ProVari. They need to be tipped up to get the liquid to the wick. On an eGo type batt thats fine - but it's awkward holding a ProVari with the end pointing up.