If you mean the CE2 clearomizers; I've had some last for ~5-6 weeks before the heating coil broke.
To clean a clearomizer, attach it to your PV and CAREFULLY wiggle and pull up on the tube to remove it from the base. Remove from the PV, rinse with hot water, blot the wick dry with a paper and blow out any water in the air tube. Put it back on the PV and apply voltage to it for ~2 seconds or until the coil glows. Repeat until any 'gunk' left on it burns away; 3 to 5 times should be sufficient. Don't do this for too long at a time, you could burn out the coil.
At this point, I just blow onto the coil to remove anything left behind, replace the tube (don't pinch the ends of the wick between the tube and the base) and make sure it's seated securely. Replace the silicone seals, being sure to line up the wick cut-outs on the cup seal with the wicks. Fill and enjoy.
HTH