I've been using a tank for months, and they really can be pretty much fiddle-free, simply expected to work (and they do).
I've had consistently positive results since starting to use a carto tank. I vape VV/HV, slotted coolcarts have given me very good results. (Not sure if the coolcarts are available in bare stainless, mine I had to peel the wrappers and sand off the glue.) I vape a moderately thin eliquid, single slot the carto, about 1/8" x 1/3", with a dremel tube cutter wheel.
I top off the tank a couple times during a day (I vape 6ml+/day), change cartos every 3 - 4 days (22 - 24ml on a carto, same as before I started using a tank). No leaks, no inhaling eliquid, it just plain works. I haven't run across any myself, in over 5 months, but I do know that sometimes a person will get a bad carto (or even several), something about the manufacturing that does throw it off of the norm; in that case you may hit a leaker, or something that just doesn't play well in a tank, though if used just as a straight carto it may be okay. (I mentioned the V4L coolcarts because they have been consistent good performers.) I suspect part of why I've been a happy camper is that I went the dremel route, stayed with it, so I get consistent slots and never cut deeply into the filler.
The time I spend slotting a carto is definitely less than the time I would spend topping it off as a bare carto, and not having to refill anywhere near as often is a huge plus.
Net, if you vape a significant amount of eliquid, have an all-day vape, tanks are really worthwhile. Find a good carto, find a punching/slotting method that you can do consistently, and enjoy the pleasure of every puff being pleasant