I would use the 8.8's if it was something I was in the middle of now, then when the 10.9's come in, just change them out one at a time. Normal driving shouldn't put that much strain on the bolts. Besides, the shear rating is of a single bolt in a test rig, you're using multiple bolts and you also have the friction of the two items mating surfaces that are bolted together.

-Todd
1987 Montero 2.6l 5-speed (Sold...but I still miss her)
2008 Jeep Patriot Sport 4x4