Quite good thing!...
However the device is equal to PCI-modems - i.e. gets CPU resources, sometimes it works quite weird: hangs-up, sometimes No Connection status, etc., - but it shows real 45Kbps !!! Moreover, I am using it for last eight months as effective ADSL-backup solution, - and it is really great!... for equivalent of $10.
So, advantages are: quite fast & cheap solution, especially as backup for faster access to Internet.
Disadvantages as for PCI-modems: CPU resources consumption, threats of hang-ups, etc.