There is not a whole lot of information on the sticks out there. What I was able to find is that they are reacting a metal, most likely magnesium with the water forming free hydrogen that escapes and a hydroxide that remains. This explains the really high pH, above 10, which is not safe.
As far as I am concerned people are being misled. And they are using bogus sales tools like ORP to make the product sound more impressive. The sites claim that the free hydrogen is mopping up the free oxygen, which is a free radical. Whether or not this is true is hard to say since hydrogen and oxygen react to form water, yet the hydrogen gas is quickly escaping. Regardless the most important thing to remember is that they are forming hydroxides, which are some of the strongest free radicals known! Therefore I feel that the claims being made are very misleading since they are not really reducing the free radical activity of the water. If anything they are increasing it. To understand how damaging hydroxides are to the tissues consider how much damage is done to the tissue when it comes in to contact with lyes (sodium hydroxide, potassium hydroxide). Calcium hydroxide (lime) is a weaker hydroxide but it still chemically burns tissues it comes in to contact with. Magnesium hydroxide is commonly sold as Milk of Magnesia, and works as a laxative because it chemically burns the intestinal wall. This causes an influx of water in to the intestines and increased peristalsis. Although chemically burning the tissues repeatedly significantly increases the risk of cancers to those tissues.
Another serious problem with the ingestion of hydroxides is that they neutralize the stomach acid. We need our stomach acid to protect us from pathogens, to properly digest proteins that can otherwise lead to allergies, to absorb minerals and some vitamins and to reduce fermentation and acid reflux. Therefore neutralizing the stomach acid can lead to nutritional deficiencies, allergies, bone loss, acid reflux, increased risk of heart disease from higher homocysteine levels and more infections.