Hot take: I chose to hand-set a 200-foot cedar fence line instead of using a power auger.
Everyone on the crew thought I was crazy for digging 40 post holes by hand for a job in Eugene, but I wanted to feel the soil layers and avoid hitting any hidden utilities. It added a full day to the project, but we found a massive, unmapped rock cluster that would have wrecked a machine bit. Has anyone else ever gone manual for better control on a tricky site?
Smart move on the cedar fence. Did something similar on a sloped property last year. Marked each spot with spray paint, then used a manual post hole digger with the clamshell head. Lets you feel for roots and rocks before you commit. Saved a rental fee and a ton of hassle with the grade changes.