My story. I started running in 1971 as a 12 year old. I was always injured- "runner's knee", Sciatic Nerve, back problems, shin problems- all the classic overuse injures. I ran when I could, didn't when I absolutely couldn't. FInally, in about 1980 I quit out of frustration. Started running again in 82, got in shape and same problems. In 84 I tore my plantar fascia. Was about to give up when a friend suggested a podiatrist and orthotics.
My orthotics came in the day of the Pole Vault in the 84 Olympics (I just seem to remember that). I have worn orthotics with shoes that would be considered stable (not motion control). I have not had an overuse injury since then. I swear this is the truth. I have had running related injuries, but not overuse injuries. I replace them every year and I wear them whenever I have shoes on my feet. I don't wear sandals because I just don't like the "look" of sandals- my own preference.
I swear by my orthotics and have friends and I coach kids in the same situation.
I could positively say that I would not be running today if I had never gotten orthotics.
It's up to you. I have also heard of people they do not help. Th ones I've known personally simply went without them too often and thier injuries occured because of everyday walking around in shoes that were not designed for healthy humans.