I will say that with the Engine Mini I first used the included dual coils, which came out at .17 Ohms. I did not like the result at all. The tank got very hot, and spit back in a nasty way. The flavor was deficient. I thought oh well, this was not a good purchase.
I trashed those coils, and popped in two Tiger coils that I had on hand from a Demon killer 8 in 1 pack of coils. These came out at .35 Ohms for the dual coils. At 54 Watts it is like a completely different tank. It has 3 times the flavor, dense and brings out the best in a juice. Most surprising is that it does not get nearly as hot, and does not spit back. What a difference coils can make!