Well, after one month, I have to say that I am still impressed with this little powerhouse! I got up at 8:00, filled my tank and screwed it on to a freshly charged battery. I put the spare batt in my pocket along with a bottle of juice and started the day with a 3 hour drive to go empty out a storage unit that I don't need. I am not a chain vaper, but I do use it frequently... I got home at around midnight after the 3 hour return trip home, and a light bulb appeared over my head. My tank was almost empty, but I had not changed batteries or fiddled with a juice bottle all day!
This is what I want in an e-cig... simple and long lasting. The coils are a breeze to change, and clean up nicely with a soak in hot water and polident, followed by a rinse and a dry burn (I remove the rubber cap, soak them in the polident, rinse them in plain water, blot everything dry with a paper towel, dry burn, then put the caps back on).
The only two negatives that I can find are:
1) The coils/wicks gunk up with dark, sweet juices rather quickly. I can do 4-6 refills with a clear 70/30 pg/vg Cherry Cough Drop from Tasty Vapor and the coil still works like a champ. Boston Cream Pie, OTOH, usually lasts through only 2 refills before you have to switch coils to regain flavor or cancel out "off taste".
2) Be careful not to drop the assembled unit on a hard surface... I have already lost one tank due to the threads separating from the base of the tank. Entirely my fault, but due to the plastic threads vs. metal on other systems, these tanks can't take many direct hits before they lose enough thread to make them impossible to catch on the female thread on the battery. I'm ordering 2 more tanks and vowing to be much more careful with them.
YMMV, but I've found a great system as a go-to while I think about exploring the world of mods, VV, and rebuildables. I never want to use a cartomizer again!