I'm looking to start giving my Labs some sort of supplement to help their joints.  No major problems with either dog apart from a little stiffness if they have to get out of their beds in the evenings.

I've heard about Devils Claw and Greenlipped mussel and wondered if these might be useful for the dogs.

Anybody used these?    Any recommendations?

Thanks in advance

I would go for Pernaton Green lipped mussell and fish oils for their anti-inflammatory effect.  I get my fish oils from Higher Nature as they are naturally sourced.

I've got some Joint-Aid for my 8 year old, he is showing no signs of slowing down at all, but thought it was about time I started supplementing to make sure he didn't get stiff!

Cortaflex, the liquid gets into the sytem quicker than tablets, and healthspan do a supplement for pets.

Well, I've just been into Holland & Barratt and the very helpful assistant advised both the Greenlipped mussel and Devils Claw..  She said to give one Devils Claw as it's anti inflamatory and two of the GLM because these help to repair.
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She seemed very confident in what she was saying so I've gone with this advise (Buy one get one half price too!). 

Does this sound okay?

I've given the dogs some joint tablets before that had Gloucosmine and Chrondroitin but didn't see any difference at all.

you need to give the dogs gloucosmine and  Chrondroitin for about 6 weeks at least before seeing any difference. The liquid form is much quicker.