In some areas I think they would be great but where I hunt, some coyotes have learned to associate ATVs with humans which means danger. When ATVs are in the woods my calling success drops. Therefore, I don't use one. I do a lot of walking, moving quietly as possible from stand to stand. ATVs will cover more ground faster and get you into places other hunters may not go. Your hunting success may all depend on location and the amount of off road traffic the critters are used to.
I'd stay away from them. Setting up quietly is the number one thing that I see beginners do incorrectly. Most think that they're calling coyotes in from a mile away and they won't be able to hear them getting set up. Others let everything "settle down" once they get to their stand before calling.
Get into that stand quietly and you'll be amazed at how many coyotes show up in the first minute of calling. Make too much noise and those animals are long gone.
One time I called in a grey fox and a bobcat from the same stand 2 minutes after a couple of dirtbike riders went by.
I have an ATV that I will be using in the local mountains out where I live. I think out here in So.Cal. they are used to the traffic on ATV's and dirtbikes. In other places it might be different.