I've got R&G bungs for the 749. I only use them on the trackday fairing, and fortunate I do because I had a low-side off at Snetterton and they saved the bike. Minimal damage, most expensive replacement was a new bung at £26! The whole kit for 749/999 costs £180ish which seems dear but it's a couple of lumps of aluminium which bolt to the sides of the engine mount/frame and then the bungs that go into those. Pretty substantial, and the forces are disipaited through several areas which seems to avoid any frame damage.
This was the result of the low side. Half the crash bung ground away, ball end broken off the lever, stainless steel bar end scuffed a little (still using it), billet clutch cover chamfered a bit (still using it, painted the damage black), underside of flip up footpeg ground away (sitll using it, good talking point!), seat unit slight damage.
After much soul searching I ended up going the full hog with R&G crash bungs.
I've got the frame set like HW and also fitted the front and rear spindle bungs as well.
I used to work as a turner in an engineering shop specialising in bikes (Metmachex), not an expert but do know a little about engineering.
The R&G kit is very well made and as good as it gets.
The frame kit is very well designed and uses the engine mount and a clamp around the frame with plenty of metal to give support.
I'm sure a big "off" will still wreck the bike, but, I do feel that a moderate low side or the bike falling over would be OK.
I like that I can take the frame bung off, but, leave all the bracket work in place. Therefore, holes in the track fairing for the bung and no hole in the road fairing.
I am sure that my off could have been totally different and been much more serious. If I'd highsided it then I feel sure they would not have helped. As it was I went down on some coolant on a corner so it just slid out from under me. As I said, the most expensive bit was the new bung and bolt! Very lucky I'd say.