Well, my plan is to use the plug kit first, and then resort to the TireFix as a last resort.
The manual says the TireFix compound can be simply peeled out of the tire and discarded. I would assume it can be peeled off the tire sensor head as well.
I haven't had any experience with the TireFix kit, but figured it was a good option to have as a backup.
I think using "Slime" or some of the other products might be a problem with the tire sensors, but from reading the manual, there should be no problem with the TireFix liquid. They don't say it on the canister, but I suspect it is a water based material, especially since they say the material can be peeled out of the tire and discarded when the tire is repaired with a patch from the inside.
When I get my new bottle of TireFix, I will open the old bottle and experiment with the material and see just how it behaves.