I don't often post but I could not resist this one.
Sheet wing stunt models( the all sheet) Gieseke Nobler and Bandalero, were first developed by Frank Coombs in South Australia in the late 70s.
These flew very well and are an ideal model to learn and improve the pattern.
Frank subsequently developed the ideas and came up with the Yardstick
which another South Australian Leon Baird refined (and later kitted), placing
in the top 10 in the Aussie Nats which Big Art attended. (I'm not sure of the year
as I wasn't there). Leon's model still exist and flies well despite several 'write
offs' where the repair involves only epoxy and a little extra glass cloth reinforcement.
The Stunt Wind mention is basically a copy (notice I didn't say ripoff although
it wouldn't be an unfair comment). I know this as I have both plans and the Yardstick predates the Stunt Wind by 7 or eight years.
The bottom line with the sheet wing stunters is that they must be light. You must use contest grade light wood and must set up the controls as per the plan.
The Yard Stick uses a large bellcrank and 'correct' geometry long throw horns,
and a chicken hopper tank. Change any thing and you 'stuff up' the concept.
As Phil mentioned the all sheet wings are prone to stalling if the corner is banged really hard. However they do recover if you let them fly out of the mess.
As I said they need to be built as per Frank's concept other wise they become very ordinary. I designed my own without heeding Franks design principals and suffered an inferior model. I'm going to build a Yard Stick properly even though I now fly the pattern confidently if not that competently just to see what I was missing. These models are suitable for raw beginner fliers yet still competitive in most local competitions
If you want to find out more there is plenty of info at
http://www.vicstunt.com/, see the 'History' section, scrolling down to "Yard Stick"