My 7 year old is limping a lot and the vet has indicated this is the onset of arthritis.  We are using cortaflex and painkillers when it gets bad but I am keen to up the preventative and damage limitation efforts (like cortaflex).

does anyone have any recommendations for good magnetic collars?  hyperdrug have one for less than £15 yet one I have seen from magnapulse is nearly £30.  does price give any indication of the effectiveness?  I use a magnetic bracelet myself but they don't sell pet collars in this place.

I would not be without my girls Bioflow collar, it has made a huge difference to my old girls stiffness

Why not give Cartrophen a go? It is a course of 4 injections, given a week apart and with some dogs it is like a miracle cure. There are also those for whom it has no benefit. Not very expensive (there's a first) Why not discuss it with your vet or Google it? It worked so well for one of my girls but did nothing for the other.

Another vote for Bioflow here too. Used them on 2 dogs and noticed a difference in both.

Recently I saw another vet at the practice (usual vet on holiday) and noticed she was wearing one of their bracelets and asked her what she thought of it because I am thinking of getting one myself. She said she wouldn't be without it now and if she takes it off and forgets to put it back on she really notices a difference. She also said she saw them used them when she was a farm vet during lambing when lambs were born with legs that wouldn't straighten (sorry... only know what she meant from her demonstrating and can't describe well) she said that with the Bioflow the leg problems would rectify usually within days and that's what made her get one herself, seeing them work on animals (her logic was, it can't be the placebo effect animals can't possibly know).

They cost more but they work wonders and in my opinion are worth it. I wouldn't use any other kind personally.

I used Bioflow on my elderly Beardie and found it made a difference

Bioflow!  I've seen it make a huge difference in many cases.

Everyone I know who rates them has a bioflow one - I have one myself but it didn't help me but I do know of people who swear by it for their dogs

By a clear majority it looks like it will be a bioflow collar.  Thanks everyone.