I side with Bruce. It's pretty obvious to me that FES is the better choice.. I believe Bruce left off the most important advantage of FES...

That being the higher inherent reliability of operation. I can't prove it, but my own feeling is that FES would be an order of magnitude more reliable in starting up. And you'll know much more quickly whether it did or did not. The only real downside to FES is the drag that the folded props will introduce. I'm thinking that the tactical benefit of having a reliable motor escape will prove to be well worth the small added drag over the course of a multi-day event.