Yeah, but I have an iPhone which maxes out at 7.5W and really going to use it at night time by the bedside.But isnt 10W very less ? These days 25W is standard with expensive devices going on to 65W chargers also
The higher wattage chargers are simply going to kill the battery. At the end of the day, physics and chemistry dictates that the battery will be heated to a much higher temperature with higher voltage, thereby accelerating its degradation. Also, the efficiency of wireless charging is quite poor as it requires a 18W charger to effectively provide 7.5W.
If your life doesn't require you to charge the battery to 80% in 30 minutes, then it is better to go with a lower wattage charger. Only use fast charging if you really need it. Too bad that most manufacturers have taken out the option of slow charging.