I like and dislike cartomizers, cartridge/atty and tanks. LOL
Cartomizers I like because I can get them color coordinated with my batteries (I know it sounds a bit superficial but hey, that's just the way it is!) and because they just plain do not leak (at least most don't). They can be the most convenient option. It's pretty easy to throw a couple of charged XL batteries and a 5-pack of cartos in my purse.
I dislike them because unless I spend a lot of money on some of the aftermarket ones, they do not give adequate visible vapor production and I end up burning a hole through the wick within a day due to my specific method of usage. When I burn a hole through the wick, I end up getting juice in my mouth. Also, many of the aftermarket ones (those with the best performance) require specialized methods of filling (weird ends on your syringe, dismantling piece by piece with a bent paperclip, etc.). They are just plain a pain. Many of the more advanced ones requiring the special filling also seem to LEAK which I dislike.
I don't mind the expense TOO much, but for daily use given my vaping technique they don't work for me. They are convenient but I seem to be forced to choose between short life and suboptimal performance or longer life and better performance but difficult and leaky. I also prefer higher VG in my juice and that doesn't wick well in most cartos.
I like cartridges/attys because attys seem to last me nearly forever. (That is, the 510 and 901 atties last me forever. The BE112/RN4072 atties don't last long before acquiring a burnt taste.) The cartridges last forever too and can be refilled in a jiffy with some polyfill, scissors and tweezers. I have literally never had to replace a 510 atty or a 901 atty (used with kr808d-1 battery). I do have to clean them occasionally. As long as you keep the cartridges topped up and not over-filled, they have good flavor &c.
I dislike cartridges/attys because you have to keep a dropper bottle handy constantly. Maybe not constantly, but after the equivalent of 4-6 cigarettes you have to top it up to keep from burning the polyfill. When switching flavors you have an unpleasant period of betwixt and between. If you overfill them on an auto system, you can ruin your battery. Also, if you don't keep it at just the right level of dampness, it will leak. Agh!
I like my tank systems (510-T and BE112T) because they give truly excellent flavor and great vapor production. Both work way better than I ever expected with auto batteries because I use manuals in other cases. Cartridges can be re-used many times so they are cost effective and again ... the flavor is really excellent.
I dislike my tank systems because I do not like having to use a syringe (510-T) to refill. There is just no way to use a syringe outside of your own home where it won't attract unwanted notice and require explanation. I have since found replacement tops for the 510-T, but until I found those they leaked for any subsequent uses after the first. The BE-112Tdoesn't require a syringe to fill, thank goodness, but after one use you need to replace the rubber cap on the cartridge to prevent unwanted leaks. I also don't like that the tank style atties are more prone to acquire burnt flavor thereby requiring replacement.
So in other words, I have no opinion. LOL