I have tried it, and my experience is that it has limited benefits for the cost.
I luckily do not suffer pain as an effect, but have heard that the Indica variety helps a lot with this. I only used Sativa variety @ between 3.5-5% concentration for relaxation and cognitive effects, and sadly I did not see any improvement having used it at a rate of about 5 drops/day for 4-5 months. However, many people DO notice a difference anecdotally, so it is a try and see situation.
If anything, it seemed to accelerate my tremours down my arms more, not sure if this showed neuroplasticity effects it was having on my body or what, but it made me jittery. It is a lovely taste if you get the natural un-refined stuff, and I think it has a general positive effect, but I have discontinued it as I cannot see justification for it.