I was a manual vacuum holdout for years because I figured “it’s just sucking up dirt, how different can it be?”
The honest answer is yes, it saves time, but mostly your time, not necessarily total cleaning cycle time. A robot might run 2 to 3 hours, but you’re not standing there guiding it. With a manual vac I’d lose 45 minutes to an hour of my Saturday actually pushing it around and watching the hose.
Where I noticed the biggest difference was consistency. I run my robot every few days now because it’s easy. When I was manual only, I’d wait until I could see debris. That meant more buildup, higher chlorine demand, and filter pressure creeping up faster. Once debris gets stirred up and removed regularly, the whole pool behaves better.
It’s not perfect though. Steps, tight corners, and behind ladders still need a brush or occasional touch-up. And if your water chemistry or circulation isn’t dialed in, a robot won’t compensate for that.
For me it turned vacuuming from “a job I avoid” into “a button I press.” That’s where the real time savings are. If you value not babysitting a hose for an hour, it’s worth it.