Not sure about the rest but this isn't too hard to answer: Most HSDPA gives a theoretical max of 7.2Mbit/s, that is 900kB/s. Don't count on actually getting out more than half of that reliably, though (in Sweden they're only allowed to advertise that as "up to 6Mbit/s" due to the overhead etc). Regular 3G is 384 kbit/s max.