My UL 450 has an L/D of 17:1 and a pretty low sink rate according to the manual and an English flight review.
"The performance is bordering on that of a motor glider and soaring flights should be a real possibility, both thermal and wave soaring."
http://www.bmaa.org/files/jabiru_ul.pdf
What is the L/D of the Savannah Kyle? Although it shouldn't matter since 912's never ever fail for any reason ever.
Regards, Laurie