The main feature:
1) coil head and metal base could be detachable.
2) coil head could be replaceable. You could only change the coil head to make the cost lowest.
CE5+ VS CE4+
1) CE4+ the metal base cannot be detachable.
2) CE4+ cannot be changed the coil head. If broken, you have to take off the whole CE4+.
CE6 VS CE5
1) CE5 the whole design is not convenient for users.
2) CE5 the changeable coil is not such elegant.
1) there are two drip tips, round and flat for your choice.
2) it can be screwed on all eGo series batteries and all 510 series batteries.