I've been exclusively using Go-Go's for the past 4 months or so, and TV juices are my favs... I find that some juices do better than others with the Go-Go, for sure. For instance, when I'm vaping my current-favorite juice, which is TV Cherry Cough Drop (sweetened), I find that I can vape about 6ml of that juice in a Go-Go cart before it gets to the point that it tastes too crappy to carry on. I've tried cleaning the Go-Go carts when I get to this point, but haven't had any success.
So, for me, I end up vaping a single Go-Go cart for about 4 days and then putting it in a pile of "dead" carts. I keep thinking I'll take an afternoon to try a few more cleaning methods to bring these "dead" carts back to life but I haven't gotten around to it.
Considering standard KR808 carts hold 1ml of juice, the above situation is the equivalent of re-filling a KR808 cart 6 times before trashing it. Not too bad, IMO. The Go-Go carts are a bit more expensive (maybe 50% more expensive than a KR808 blank).
All things considered, tho, the Go-Go delivers better flavor, requires less fiddling and refilling, and the batteries last like 3 times longer than a standard KR808.
FWIW - I've found that some other juices (ones that don't have sucralose sweetener???) can be vaped in a single Go-Go cart for a VERY long time - like 20ml vaped in a single cart before it "goes bad". But none of them are TV juices.