Ended up taking mine with me to Lerderderg this weekend, I'm confident enough to share some words about the stove for others who might be thinking of checking one out themselves.

First thing - first attempt using the stove resulted in a blockage that took some time to clear out. Turns out that these stoves, in the fuel tank, there may be some remnants from the manufacturing process left behind. If you run this stove without thoroughly washing it out, this can result in a blockage. I unblocked mine by flushing it out, and manually cleaning the jet. Worked a charm since then.
As for fuels, I used Shellite to start with, which strangely enough, was not capable of boiling a litre of water in under ten minutes. I could boil less, but a litre just did not want to boil.
Using Kerosene, it boiled a litre of water within about 5 minutes (well over the 3.5 minutes that Optimus quote).
The only problem with using Kerosene is that priming is messy business, and can be dangerous, so I'd recommend carrying some spirits to prime the stove.
The stove is far from perfect, however it was reliable, and that is why I got mine. Having used the older Optimus stoves back in the 80's and early 90's, these things, permitting they are maintained well, are bomb proof.
The main concern that I have is that they are a menace when there is even so much as a little wind. Even so much as a breeze will send the flame away from the pot, push your boil times through the roof, and even worse, set fire to any loose leaf litter or grass nearby.
With that said, it would be common sense to be careful as to where to use one of these.
As for burn time, I cooked multiple coffees, dinner (25 minutes cooking time), soup, breakfast, and boiled a few litres of water for drinking. At the end of the trip, I had at least half a tank left, which was full to 3/4. Its pretty efficient, at least, more so than my Whisperlite.
The stove itself is pretty heavy, with a full tank, its just under 2kg, so definitely not for those who are trying to carry less. That said, carrying this and everything else this weekend (including water) my pack weight was well under 15 kg, so its not that bad.
End of the day, pretty happy with it. It is what it is. I'd probably want to get a service kit for it, just in case of more blockages, and I'd be keen to see how other fuels work with it, and how they affect boil times.
If there's anything that anyone else wants to know, feel free to ask.