Oh man - and I forgot to mention that if you haven't already tried them, the tips in
this thread will speed up OmniFocus' sync as much as possible, regardless of what sync method you're using.
Our goal with regards to sync speed is to have it be acceptably fast even over an EDGE cell phone connection. (Your home connection is almost certainly faster than that.)
In any case, if your syncs with our server are taking much more than 10 seconds or so, that's something we'd want to investigate...