Curious if anyone has used the various LED/Red light therapy products on the market. My older horse has some arthritis and although he has KS surgery, still tends to get tight in his back. I have a pretty thorough regime but I was curious about light therapy to put on his back and hocks before and after rides to help get him loosened up and feeling good, especially in the winter.

Yes. The problem with light therapy is it is only skin deep and should be used to activate acupuncture points. It doesn't go deep enough to directly help muscle tissue . There's a big difference in laser therapy and red or green light therapy. Green/blue light is highly refractive, red light is more focused. Different types of lasers can go a few inches into tissue. 
PEMF is going to go the deepest and help blood flow at a cellular level. 

Well said.

I use a true cold laser on muscle pain for myself.  It is effective but it does nothing for my arthritic old joints except help with the inflammation around the joints.  If you live near Oklahoma City I would loan you mine to try.   One thing I learned about the lasers is that pulsed light is more effective than just straight light.  

According to my vet, the lights and lasers sold to individuals aren't strong enough to help much. You have to go to a vet for the good treatment.

Red lights are a lot different (and way cheaper) than a laser. Depends on what you're working on. Red light therapy isn't much more than working with a flash light and red lense. Lasers are available in various strengths (Class 1-4) . You can buy a decent laser for $6500 and a very good ine for twice that.
Since I've got my MagnaWave I have no need anymore for my laser or Ted light.