I haven't had any negative experiences using a Thermacell, but that really doesn't answer your specific question. My experience with the Thermacell also evidently doesn't account for negative encounters that were outside of my vision, although if I'm using a Thermacell the bugs are bad enough that I probably wouldn't be out otherwise, so there's that... Permethrin/Permanone works for ticks, and is odorless when dry, as the propellant contains the odor.
I do know people who use them for spring bear in Canada, so that should say something.