Can anyone help me with this query?

I am thinking of buying two tiny B&W 686 speakers and an ASW608 subwoofer. The sales person in the shop recommended i get a Podspeaker Dock to go with it (Link below)

http://www1.electronichouse.com/prod.../253/5500.html

I don't know a huge amount about amps and speakers, but I still find it difficult to believe that this tiny amp will be enough to power two speakers and a subwoofer.

If anyone here has any experience with The Dock, please let me know what you think! And if anyone else has a suggestion for a good shelf ipod dock amplifier, please do holla too!

Many thanks in advance!