A CE4 comes with it's own proprietary drip tip. There are adapters out there to allow you to put your own drip tip on it if you wish. I couldn't tell you the lifespan as all of mine leaked or cracked long before the atomizer burned out, but I would say a good quality atomizer will outlast just about anything out there that isn't rebuildable or at least has replaceable atomizers.
Direct dripping on a standard atty will give you ten puffs or so. It depends on how long a draw you take and how much you pre-heat the juice (if using a manual) before taking a draw. Flavor is much better than anything else though, as is throat hit.