I've used a lot of free woodchips.
First: don't leave a big pile sitting for days, waiting to be spread out. I almost had a fire from spontaneous combustion. Yes, that's a real thing. Spread them out right away.
Some plants showed signs of nitrogen deficiency the second year. I sprinkled on a very small amount of ammonium sulfate, once, that took care of it.
Slime mold likes wood chips! And I like slime mold. Don't be surprised if you see some. It's fascinating stuff.
Wind, rain and decomposition have removed most of the chips, but it took several years. You may need a refresher eventually.
My small dogs didn't like walking on them at first, but the chips softened up pretty fast.
If possible, find out where the chips are from. Don't get them during Siberian Elm seed season. Avoid chips that came from diseased or insect infested plants. Try to have a friendly relationship with your chip provider so you can get a good clean load.
I like the wood chips way better than a rock covering, and highly recommend them.
