La Ruta de los Conquistadores

in a drunken, overly expectant(of my abilities) internet moment, i signed up for this race early this year. it is now at that moment where i need to make my decision. do i defer to next year, possibly losing 50% of my entry fee by the time i do so, or do i book the meager $350 airfare(round trip!!!), request a leave of absence for a week from work, and go ride till i fall over? i have 1.75 vacation days left at work, so i won't be getting paid while i'm down there. i am definitely not in the shape to be putting out a strong, continuous effort for 4 days straight. i am, however, confident in my ability to just grind through anything with dumb perseverance. i am in really good shape in general, and my riding is good enough to get through with frequent breaks. i speak a little spanish, and i would love to see costa rica. if i don't go, and defer to next year after the 100% cutoff, i lose around $500, at least. this is my dilema.