Assuming that you'll be on a narrowbody Airbus (A319/320) you'll get the bigger seat, free alcohol/premium beverages, and a meal. No IFE. No in-seat power for a laptop or other personal entertainment device. In coach you get the smaller seat/less personal space, possibly buy on board food if they don't run out before getting to you, standard non-alcoholic beverages (premium beverages/snacks are for purchase), no IFE or in-seat power. The FA(s) working either cabin can make or break the experience. Whether it is worth 17.5K miles to be up front is up to you. Remember that you can purchase the "goFirst" upgrade if there are available seats - maybe someone else will know the cost for that flight.

Jim