Or if the design/production of certain stoves changed. Or if your problems with the Force 10 LPG stove are indicative of a particular model. Just idle curiosity, as our stove has worked very well, although admittedly we haven't used it daily for as long as you have. Still, we have used it off and on over several years before using it more intensively for seven months daily while living aboard and cruising.
I'm curious, b/c you mention a cast iron burners, and non-stainless bits (which obviously rusted). I don't think my stove has cast iron burners (I've never seen cast iron burners before), and the only non-stainless bits that I can see on it, after having installed it and cooked on it and cleaned it, are some aluminum bits. In short, I wonder if a change in company ownership resulted in a change of product manufacture/design, and quality control as well. Again, just idle curiosity, as we seem to have had pretty different experiences with the stove (and I bought mine, circa 2003 or so, after some good recommendations.)
Kind of suggests that a simple old-fashioned rugged quality Taylors paraffin stove with very few moving parts is the way to go ;-)