I have been using my ce5 now for a full week and it has been great. No leaking or perfect wicking each draw. I didnt mess with cleaning. But getting a weeks use is cost effective enough to just replace it.
I have also been using the vivinova and am frustrated with it. Screw in the head, fill'er up, screw on top and vape. The problem occurs each time I have to refill. When I screw off the top cap it also loosens the headcoil. I cant reach in far enough with my fingers to retighten it. So, each time I have to take all 3 pieces apart to add juice and reassemble nice and tight. It would be great if they could design a snap in head so it would'nt loosen each time the cap has to be removed to fill. Other than that I love the v2.5 with the longer wicks. I had problems with wicking using the short wicks.
when you put the head on takeoff the rubber cap then put something in the 2 slots ( I use the handle end of my tweezers but you could use a screwdriver or anything) and crank it down a little extra tight. Put the seal back on and put it all together and you won't have any problems with it coming loose anymore lol