My 6k PR was on a hilly-ish course but with ideal temperature (25:55)... I came through 5k around 21:42 (5k PR is 21:05).
My splits were all pretty even (I pace much better than I did in high school, wow, though could still do better). I feel like my first and last miles are usually the slowest though (I always pick it up during after mile 1 it seems and can carry that until the 5k before I start to fatigue fast...).
I'd love to sub 25:30 and I think I can do it.... My last 6k I came through the 5k even faster I think but died at end.... I ran a very conservative first mile too...
Is there room to improve?