Are they really so much heavier than, say, a stove, gas bottle and two pans?
Very much so, especially when you consider the weight of carried meths on top of the already heavy stove. I think the real weight gain comes from the windshield; it's a very big bit of metal for what can be achieved with a bit of tin foil.
But that's not the point of the SAT I guess, its completely bomb proof and above all as cheap as chips. However if your looking to do any serious hiking I'd look at another option, and I speak from experience on that one .
Are they really so much heavier than, say, a stove, gas bottle and two pans?
Yep!
I really wouldn't plan on hiking with one - the weight is going to be an issue.
Mine sat in a cupboard for years until I resurrected it for motorbike camping - where weight wasn't an issue, but space was, and for this it's ideal. It'll easily cook for two (unless you invite Ged along!), is nicely compact and it's shape means there is very little wasted space when packing motorcycle panniers - as there can be with round pots.
But if you invite Ged he'll bring his own cookset -- and his own bike.
http://www.jubileegroup.co.uk/JOS/misc/dscf3657b.jpg
... I just hadn't realised, until this thread, what a...an epicurean you were!!! ...