A:AnswerI wouldn't go anything over a 20W charger for extended periods. You "can" charge it with higher wattages, but you run the risk of overheating and battery explosion.
A:AnswerI hear you, I would love this as well. I have one in my car, but what I did was pick up a small piece of thin black adhesive vinyl from Michaels, any craft store (perhaps find this even at Walmart) Cut out a circular pattern and place it over the white magnet. It works just fine, no loss of magnet strength.
I GUESS you can even use a black Sharpie, even a paint marker...I personally havent tried that though.
