My mate's well peeved that we're not using the one gear, me too.
Looking at past results it looks like it favours the geared bikes, some very fast times have been posted so it can't be mega
I don't know the route at all, is it lots of lovely hills? I really hate spinning flat out for looong flat sections as happened in the Viking Challenge the other month when I took the single speed. Apart from a few hills and bumpy trails that suited the ss it was (to me at any rate) a geared bike event.
It can be damned annoying to overtake loads of people on the twisty / hilly stuff just to lose ground again on the flat stuff because you're revving out, but - you learn to accept that that is
one of the facets of single speeding.
So, on one hand I'd like to do as well as I could, which means going geared, on the other I'd like
to go ss but it would mean sacrificing quite a few places and expending a lot more energy to keep the tempo up if there's lots of flat stuff.