Ah, little aeroplane handling characteristics - my favourite subject to bore people about in the pub.
First thing I should admit, although there are plenty of them over here, I've not flown a Jabiru so can't offer much advice specific to that type (although I have flown a CT which I imagine is fairly similar).
Problem with a microlight/ultralight is that it has no inertia, also to some extent (although less so with a slippery beast like the Jab) it has fairly high profile drag, as well as a fair bit of induced drag at low speeds. All this means that if you want to shorten the life of the undercarriage a 1.3Vs approach is the best way to do it. With a draggier aeroplane like the Thruster, I'd fly about 1.7Vs in still conditions, rising to about 2.0Vs in very turbulent approach conditions. Now the Jabiru is not that draggy so I suspect that you may find that around 1.5Vs is closer to the mark.
Another aspect of the low-inertia / high drag is that you don't want to be starting your roundout as high as you do in, say, a C172. I'd normally in any larger microlight such as the Jabiru to be starting my roundout at about 10-15ft, which feels unnaturally low until you get used to it - particularly combined with the relatively steep approach that comes with the high approach speeds you want to be using. But, trust me, it does work.
My suggestion would be to find a nice long runway somewhere, start at around 1.7Vs(indicated) and fly circuits for a while bringing the speed down a couple of knots each time on finals until it starts to feel a little to stall, then wind it up again a little.
Another thing to be aware of is that ASIs in general, and ultralight ASIs in particular tend to underread quite a lot at low speed, so by flying 1.3Vs (indicated) you are probably actually flying slower than that. The info I've got available to me suggests that the Jabiru is stalling at around 35-37 kn CAS with full flaps.
Hope that helps a bit.
G
N.B. Do the good burgers of Bundaberg not supply a flight manual?