"The OP is not talking about RTA's, he is using factory coils from the sound of the question. I use an Ultra sonic cleaner on occasion. I had tried to clean nautilus coils in it. I find the build up of water in the coils made for a long drying time, so you wouldn't be able to just pluck your device from the cleaner and vape on. Aside from that, I found most factory type coils failed in the wicking department, not the coil itself, the ultrasound seems to have little to no effect on the wick materials cleanliness or durability."
Yup, I was not talking about them either. 3 years ago that is how I cleaned my carts and clearos. Little dish soap and water and maybe a 30 minute soak in coke. Rinse well. It so happens I clean my RTAs, RDAs and everything else even my mechs that way. There is no sense in over complicating things. Unless of course you want a gadget.
Vodka and Everclear are better for drinking. I tried the jewelry cleaner and then laughed at myself. It did nothing.