Hello Carol,
It sounds as though you are doing a really good job of managing Ozzy's symptoms and I am delighted that he is enjoying his walks. The important thing is that he gets an effective anti-inflammatory and pain management treatment such as Metacam when he needs it, and then the use of supplements may help to reduce the amount of Metacam he needs to take.
When I try to suggest evidence of effectiveness and safety is important, the main target is not people who use things like food supplements alongside drugs sensibly as part of a treatment regime, but those who shriek that everything that medical science produces is poisoning your pet and that it can all be replaced with perfectly safe, natural products. Most of the websites that do this seem to be American (so far), and it is often tied in with conspiracy theory about "Big pharma" in league with the doctors and the government to keep people buying expensive drugs. It also usually includes condemnation of vaccines (for both pets and humans) that flies in the face of all the benefits of modern medicine.
The only thing I will say is that, despite its many followers, acupuncture doesn't work. There is no physical basis for it as a treatment. There are no energy meridians in the body, no blockages of energy and no such thing as a vital energy flowing round the body. More importantly, there is no convincing evidence that it works. The problem with trying to decide what works on the basis of a single dog is that there is no control group. When properly constructed studies are performed it is found that sham acupuncture, where needles are inserted into random places on the body, is just as effective as "real" acupuncture. The only good thing about it is that it is unlikely to do any harm.
In 2013, the American Academy of Osteopathic Surgeons produced a 1200 page study of various interventions to treat osteoarthritis of the knee. They gave a strong recommendation that acupuncture was not an appropriate treatment because there was no evidence that it works. As always, people will make up their own minds.