I live in Poland. I can get ~160kb/s average download speed durning apt-get update, no matter what bandwidth is my internet connection (the best is about 50MBit -> 6Mb/s theoretically). Even update of all my repos is 150kb it takes couple of minutes, for me it is veeeery long and not power efficient(apt-get process eats lots of cpu). As I wrote in my earlier post, querying special server which knows wheter repos are updated or not, would take no longer tahn 10 sec and dozen of kb data traffic.
For you, having such weak download speed this improvement would be essential.