I use a Radioshack branded temperature control station that I have used for a good number of years now. I have also used many cheap irons of all types, and keep one in a drawer for taking on the go. In my experience, even a cheapo iron tip will last plenty long if treated properly. If you are destroying tips left and right, there is something wrong with your technique, no matter how cheap the hardware.
As soon as a tip gets contaminated, it must be cleaned and re-tinned. If the contamination is allowed to cake or remain, it will damage the surface of the tip below the tinned surface, and that's the end of your tip. They can sometimes be saved, but often can not. This is what results in the demise of most soldering tips.
As soon as you see a spot or any blackening anywhere on your tip, stop and feed fresh solder onto it until it bubbles off and there is an excessive drop of solder hanging from your tip, then roll the iron so the fresh solder coats the whole tip. If it is really carbonized, you may have to scrape it first. I use an exacto to very gently scrape the crust off. Then coat the tip in fresh solder.
If you are careful to keep your tip clean and tinned, it should last forever.
It should be noted that I do use Weller tips because they fit in my iron and are available in various profiles. They are indeed of a better quality than your usual Shack brand iron tips.
Guit Boxes: 87 MIJ Strat, Ibanez MIJ RG540, Korean Fender Dreadnaught, The Loar LH-500 (1934 L-5 Reproduction)
Amp: Marshall TSL100 amp head with JCM900 1960 Lead 4 X 12 angled cab
Effects: Crybaby, TS10 Tube Screamer, Badder Bad Monkey, Boss Metal Zone