I think cleaning atomizers is a lot easier than what I've seen of cleaning cartomizers. But if you have plenty of money to blow and want to just toss out cartomizers when they are empty you could do that, but you maybe be going through a couple per day?
With atomizers I have 3: 2 I rotate and a spare in case one fails. Every weekend I switch to my cleaned and dried atty. I put the one I used all week in a jar of alcohol, make sure it's filled with the alcohol and occasionally swish it around, next day I take it out of the alcohol, shake it out, lay it on paper towels to dry. The next weekend I switch to that clean one and drip a bit of juice on the atty to prime it.
The upside of cartos is they hold more juice so you can smoke many cigarettes' worth of juice without messing with it. If you decide to refill them (assuming you buy a unit with refillable cartos and not a rebranded unit with 1-use cartos), refilling may require a blunt or flexible syringe, using the cap to force juice in or other methods.
Cartridges (carts used with attys) need to be topped off and refilled during the day. The most equipment needed is a dropper bottle of juice and maybe an unbent paper clip for pushing up some carts or for repositioning the stuffing. Sometimes I have to mess with a cart quite a bit.
BTW - Safe cig is a jacked up rebrand of one of the same Chinese brands you can buy elsewhere cheaper. I don't know if it's a KR808D-1 or an E9 or some other carto model but $30 for a battery is about 2x to 3x as much as it should be.