I added 50 ppm Borates to my pool last year. It seems to reduce the surface tension of the water (less of a meniscus in vials when testing) and seems to make the water sparkle more. I definitely noticed that the water is far less reactive to algae growth -- I've had >3000 ppb phosphates in my pool so I've had to be careful to maintain the chlorine properly as algae can grow quickly if I don't, but since the borates I did an an experiment letting the chlorine get low and didn't notice anywhere near the same rate of dull/cloudy water development for a pending algae bloom.

I've never had a pH rise problem in my pool so didn't notice much change there -- borates are an additional pH buffer. It does seem that the pH rises more slowly and needs more acid when I do need to add it, but the result is the same total acid per unit time, just more quantity added less frequently.

As waterbear mentioned, many people have tried it and most think it's great though there are a small number who saw no benefit from their perspective.

Richard