Hunters discussing Unit 691 in Colorado highlight the challenging terrain and variable weather conditions, emphasizing the importance of preparing for steep and rugged landscapes. Many commend the unit for its promising elk populations during early and late seasons, suggesting that careful scouting and knowledge of migration patterns can enhance success. Some users advise on the strategic use of glassing from elevated positions to spot game more effectively. Overall, persistence and adaptability are key traits recommended by hunters experienced in this unit, alongside ensuring proper gear for the often unpredictable mountain environment.