ADSL is fast no matter the choice! However here are some SIMPLE guide lines:
Email and basic web surfing, 500 megs (0.5Gig) per month.
Email and basic web surfing + Skype, 1Gig per month.
Lots of downloading from the internet, possibly music/mini movies etc. This is HIGH bandwidth use. We recommend you monitor your usage to decide what is correct for your requirement or alternately contact our support line to get advice from a trained expert.
If you have multiple users at home, do the sums based on above.
Email download or Web Surfing for a 1 to 3 users simultaneously on a 384k line should be fine for majority of users.
If you can tell the difference in Internet and Email download speeds and high speed is important to you then try the bigger lines! If you are using your computer at home to Terminal Server to the office or to move larger files etc through the Internet, then 4 meg line is the only way to go.