I only use two companies for juice. V4L juices are 70% of what I vape, and TV is the other 30%. I do have a bottle of sucralose that I can use to sweeten my juices, but I've rarely used it.
My main vapes are V4L Vanilla (dark juice), V4L Butterscotch (pink juice), V4L Redcow (darkish juice), TV S'Mores (very dark), and TV Strawberry Cheesecake (very dark). I never let a cart run dry, as I throw it in my "to wash bin" as soon as I suspect flavor dropping. Sometimes they get hard to draw, but I use a straightened paperclip to clean it out and they get better again.
Now, to be fair... once I've gotten the WoW & Coolcarts in, I don't use my 2009 cartos as much anymore. It's not that they are dead, but the WoW & Coolcarts are SO much better so I use them on savory juices. The menthol/mint juices I still use the old cartos with, mostly because it's less of a TH to use those cartos, and the mint flavors are really high TH for me.
Oh, and I've gotten two clear-o-mizers, and they suck.