I bought a real expensive iron years ago because I was tired of the irons dying. The expensive one lasted about 2 weeks after the warranty and then died.
Since then, I've had 2 Black and Decker from Walmart. The last one I bought about 4 years ago for $20. It's still going strong and I use straight tap water for the steam with no problems. I figure I can buy a new cheap iron every few years and still come out ahead of buying an expensive one.