I've had ZERO issues with my USB CA-100, but yes it does go slow. I would ENTIRELY warn against the Boxwave Charge-N-Sync, I have one of these as well and the connection is INCREDIBLY finicky, I'm required to have everything just right including neutral karma and the moons in the 7th house of Jupiter before the dang thing works, and then it will charge for DAYS without ever "finishing". Also makes my N800/E51 very hot to the touch, so I don't use it except as a quick charger for the E51.