Unless you are downloading from an office with a hefty internet connection or you have a good fibre connection, it is unlikely (but not impossible) you are connected to the internet at 54MBs, this is infact the speed that your computer is connected to the wireless router.
1Mbps may be the limit of your connection, other than that, I use HTTrack and whilst it is very good, it is slow as it has to index the site and build up a list of files to download.
If you want to check for limits, before you start the download, click on
Set options... and you should be able to set any limit you want under the
Flow Control tabs.