If you are happy with your current iron then I agree with dunster - keep going with it. After all, you could buy fabric or some other quilty stuff with whatever money you might spend on a new iron ...
I love my Rowenta. It replaced a light weight plastic Sunbeam about 8 years ago. I've not had any problems with the Rowenta but it is noticeably heavier than the Sunbeam. I like the additional weight but I realize heavier irons are not an option when one has carpal tunnel or other arm/shoulder/wrist/hand injuries or issues.