Yes, making your own is best. You never know what is in store bought wood chips or mulch. They use a lot of things that should not be in a garden including coloring in the chips. Make sure to pile it up for awhile to start breaking down a bit first. They recommend not using fresh chips on the garden but to allow them to age a bit and start breaking down. You can also mix them in some compost to speed the process. I would also recommend getting some of the Mykos that I have listed in this article or some type of Mycorrhizal to add to the chips while they break down. The Mykos will spread out white veins throughout the entire pile and help to break it down quicker. Good luck!