my chargers suck. i have the usb and the ac charger. i constantly need to make sure my batteries are are extremely clean, as well as the ac connection in order for the thing to charge, i usually have to take a toothpick or scribe to clean the ac charger, because the connector is recessed. and the usb charger is so delicate, i have to spend 5 minutes setting it just right to get a good connection.. are there any other options than the standard ones you can get from cignot?