Your download speed depends a lot on the speed of the hosts you're downloading from, as well as your own speed. And even though the hosts may be showing as T1 or T3... doesn't mean that they actually have that speed (people change their speed settings within LW to try & increase their own download speed).

Download speed also depends on how many upload slots hosts have open...if they've got lots of upload slots open but not a lot of bandwidth to play with then nobody's going to get a very fast download from them!

You can help yourself out by making sure that your LW is set up for best perfomance. Have a look at the thread below, it has some really good tips
Configuring LW for best performance