I don't care too much about bi-directional sync, since I don't expect to change things on the tablet, just read them.
First is an error: "rsync error: some files could not be transferred (code 23) at main.c(1385) [generator=2. 6.9]" It doesn't look like anything is missing from the synced folders, and google tells me that code can mean all sorts of innocuous things, so I don't mind it. Just thought it was worth mentioning.
Secondly, even with the flags as set up as above -v is spitting out filenames. Is rsync just telling me what files are being checked, or is it recopying everything that's already been copied (which it shouldn't with the -u flag)? The entire action takes only a couple minutes for 1.5 GB, so I'm guessing it's the former.