CE4, Vivi Nova, iClear clearos come with top coils--which causes wicking problems because the heating coil is located on top of the tank so your juice have to travel upwards--against gravity.
I prefer bottom coils--I like Kanger and Aspire clearos a lot.
A few tips while using Kangers:
Kanger Troubleshooting 101:
If your clearo is flooding, the connections are not tight enough--or too tight. Keep reading.
If you're using clearos and getting a burnt taste it means that not enough juice is getting to the coil and you're basically vaping dry, hot air or inhaling smoke from the gunk that's burning off of your coil. Not a good thing. Another case of bad taste maybe the tank itself--some arrive covered with some kind of nasty grease; wash them with soap and water (just the tanks--soak the coils in PGA or vodka).
There are a few things you need to remember when using a T3 or an eVod or a ProTank--in addition to keeping your coils clean and free of gunk that accumulates on them.
1) Make sure that the atomizer coil is screwed into the base tightly--every time you refill; they often come not fully tightened from the manufacturer, or may have gotten loose through repeated refills.
2) Look at all the inner seals and gaskets to make sure they haven't become dislodged.
3) Make sure that you screw the tank into its base tightly. If it's not tight, it will leak.
4) When you screw your clearomizer into your battery, do not overtighten--screw it in only until it makes contact--no farther, or you may push the center post in too deep and cause all kinds of problems, including leaking. When the draw becomes tight or the taste and vapor production begin to diminish, replace the coil. This will happen sooner (even as soon as one day of heavy use) if you're using dark, viscous, or very sweet juices. The old coil can be cleaned and dry burned.
5) Make sure you're not getting any juice in the center tube when you're filling--this will cause your eVod to leak like a sieve. If some juice gets into the tube, close the top cap, place a tissue under your tank and blow gently through the clearomizer to get rid of any excess eliquid. Also, extra condensation inside the tank may, on some occasions, drip back into the center tube. Wipe your mouthpiece dry with a q-tip or a tissue when you refill (or more often when/if needed).
6) Take an occasional "primer puff" (a slow draw without activating the battery) when you vape. It helps move the juice into the coil chamber and removes any air bubbles that sometimes form in the tank and may cause gurgling or impede proper wicking.
7) Take slow long draws rather than sharp and quick ones like we used to do while smoking cigarettes. Do not over vape, chain vape, power vape. Let the juice travel to the coil between drags.
and last but not least
8) Do not remove any flavor wicks if you're experiencing any leaking or flooding. Those wicks are there for a reason. If you feel that you have to remove a wick because your eliquid is particularly thick, do it carefully--one strand at a time. If your liquid is super thin, you can thicken it with a bit of VG (USP--pharma grade) or you can add another strand of cotton to your flavor wick. Don't add too much or you'll choke your atomizer and get a dry hit.
Also, make sure you're vaping at correct wattages; I like 5.5-7 watts.
Good luck!
I aploogize. 
