Muscle stimulators work and are great for healing after i tore my acl and hyper extended my mcl do to a leg lock during a full contact sparring training it happened while trying to roll out of it
anyways i still use mine when my knee gets sore or now after my workout ill use it and i swear i recover alot faster now all you need is 10-20 minutes a day

id go with the gel type stickons over the pads you have to get wet id also try to get one with more then 4 ports that way you can do more then 1 spot at a time