Pace Bands and Pace Tats

One of my friends/running buddies sent me a link to a website that sells Pace Tattoos for race day, so runners can keep themselves on track at a steady pace to finish in their goal time. It's helpful because you can look down at every mile and know if you're ahead of or behind your overall target pace. Runner's World has a printable pace band that I think I'll try out for my 18 miler this Saturday. I'm hoping that by slowing down a little bit at the beginning and keeping a steady pace across the whole distance I can avoid bonking or having to slow down from fatigue. At the actual race, there will be pace groups for a 4hr 30min finish time and a 5hr finish time. Being reasonable and realistic, I'm hoping to finish right in between the two. Four and a half hours would be a 10:18 pace (6 seconds faster than my 17 mile run pace) and 5 hours would be slower than 11 minutes, which I feel is too slow. My only REAL goal is to come in under 5 hours, but my secondary goal is to come in between 4:30 and 4:45. I think that is completely possible for me. That would be a pace between 10:18 and 10:52. Pretty much all of my long runs end up in that window, so the biggest question is whether I can keep that pace up for an additional 9 miles above the longest run I've already done. Hopefully! I think I'll test out a 10:40 pace on Saturday. Maybe. Don't hold me to it. But whatever pace I choose, I want to practice trying to keep it steady.