I think a lotta CE3 problems are tied to gunk build up. Using only 75%+ PG, I have seen each of my CE3s build up gunk fast. I have been cleanning out every 3 refills, and dismantling every 10 fills, for a deeper clean. This includes using a plastic pick to try to scrape off some of the gunk. While this has saved the CE3s from dying prematurely, 3 still working, I think this makes them much more sensitive to voltage. I just cleaned up an old one, getting as much gunk off as I could. On a stick battery, the burned taste is tolerable. When I switched to an x2 900, it was wretched. I have one new CE3 still in the package, so I fired it up with the same juice.... It tastes great on both batteries.
I do not think that the juice I am using is making the gunk worse.... everything is 12-18 mg nic, 75-85%+ PG. I've used ECB, SI, SI-Niq, TVR... All seem to give the same results.
WHile I love the performance of the CE3 out of the box, I am really disappointed by the short life of the product. I have another box unopened, and I guess I will use it and enjoy it while it lasts. Including frequent cleaning, 5-10 fills before sudden death or burned taste is not worth the expense.
EDIT: At least for me, the clearos have lasted a little better. Here's hoping that T3s are available soon to try.