Any advantages to bi-wiring speakers vs. single

Usually it is well worth it. I can't speak for your speakers specifically but the several pair I have owned over many years have mostly been bi-wire and each of them have appreciated it. It also adds the freedom of bi-amping which opens up even more thrilling options. Plus, there's no harm done with the extra terminals except for the bit of extra $$$. Go with the bi-wire.

Bi-wiring usually lets more cable reach your drivers...whether that's necessarily always a good thing depends on your speakers? I have found when I bi-wire with 2 sets of the exact same cable there tends to be overall improvement and what I like is using 2 different cables for each driver and in so doing I can tailor each cable "synergistically" with each (much like power cords or different I/C's in your system). My Silverline Sonata 2's were bi-wired as such, much to their benefit. My 2 cents.. (again).