I've had a target mini for just over a month. At first I used it exclusively in Temp Control mode, usually around 250-275. Now I vape in Wattage Mode all the time. Much better control. Kind of like driving an automatic and switching to standard transmission, for lack of a better description. I vary the wattage depending on what I'm vaping. I usually vape 80VG and tend to stay between 25-28 watts. If I was vaping a higher PG juice I'd probably reduce the watts a bit. You have to experiment to find the most satisfying setting.
When you put a new coil in, start off very low, (I start at 15 watts) whether you're using Watts or Temp. Be sure to prime the coil well and when you start using it, take frequent small draws. In between, take deep draws without hitting the fire button in order to get the ceramic saturated. Gradually increase your Watts/Temp. The ceramic coils can be finicky so don't rush it unless you're sure that it's priming quickly. This method works great for me.